Deprecation warnings re: Dart 2.0.0

[jcavena]

Builds are showing a bunch of deprecation warnings for / division outside of calc() in our SASS files.

DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div($spacer, 2) or calc($spacer / 2)
More info and automated migrator: https://sass-lang.com/d/slash-div
    ╷
298 │ $headings-margin-bottom:      $spacer / 2 !default;
    │                               ^^^^^^^^^^^
    ╵
    node_modules/bootstrap/scss/_variables.scss 298:31  @import
    node_modules/bootstrap/scss/bootstrap.scss 9:9      root stylesheet
DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div($input-padding-y, 2) or calc($input-padding-y / 2)
More info and automated migrator: https://sass-lang.com/d/slash-div
    ╷
493 │ $input-height-inner-quarter:            calc(#{$input-line-height * .25em} + #{$input-padding-y / 2}) !default;
    │                                                                                ^^^^^^^^^^^^^^^^^^^^
    ╵
    node_modules/bootstrap/scss/_variables.scss 493:80  @import
    node_modules/bootstrap/scss/bootstrap.scss 9:9      root stylesheet
DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div($custom-control-indicator-size, 2) or calc($custom-control-indicator-size / 2)
More info and automated migrator: https://sass-lang.com/d/slash-div
    ╷
560 │ $custom-switch-indicator-border-radius:         $custom-control-indicator-size / 2 !default;
    │                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    ╵
    node_modules/bootstrap/scss/_variables.scss 560:49  @import
    node_modules/bootstrap/scss/bootstrap.scss 9:9      root stylesheet
DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div($spacer, 2) or calc($spacer / 2)
More info and automated migrator: https://sass-lang.com/d/slash-div
    ╷
706 │ $nav-divider-margin-y:              $spacer / 2 !default;
    │                                     ^^^^^^^^^^^
    ╵
    node_modules/bootstrap/scss/_variables.scss 706:37  @import
    node_modules/bootstrap/scss/bootstrap.scss 9:9      root stylesheet
DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div($spacer, 2) or calc($spacer / 2)
More info and automated migrator: https://sass-lang.com/d/slash-div
    ╷
711 │ $navbar-padding-y:                  $spacer / 2 !default;
    │                                     ^^^^^^^^^^^
    ╵
    node_modules/bootstrap/scss/_variables.scss 711:37  @import
    node_modules/bootstrap/scss/bootstrap.scss 9:9      root stylesheet
WARNING: 58 repetitive deprecation warnings omitted.
DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div(20em, 16) or calc(20em / 16)
More info and automated migrator: https://sass-lang.com/d/slash-div
   ╷
11 │ $fa-fw-width:                 (20em / 16);
   │                                ^^^^^^^^^
   ╵
    node_modules/@fortawesome/fontawesome-free/scss/_variables.scss 11:32  @import
    node_modules/@fortawesome/fontawesome-free/scss/fontawesome.scss 5:9   @import
    app/javascript/pay/style.scss 2:9                                      root stylesheet
DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div(4em, 3) or calc(4em / 3)
More info and automated migrator: https://sass-lang.com/d/slash-div
  ╷
6 │   font-size: (4em / 3);
  │               ^^^^^^^
  ╵
    node_modules/@fortawesome/fontawesome-free/scss/_larger.scss 6:15     @import
    node_modules/@fortawesome/fontawesome-free/scss/fontawesome.scss 8:9  @import
    app/javascript/pay/style.scss 2:9                                     root stylesheet
DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div(3em, 4) or calc(3em / 4)
More info and automated migrator: https://sass-lang.com/d/slash-div
  ╷
7 │   line-height: (3em / 4);
  │                 ^^^^^^^
  ╵
    node_modules/@fortawesome/fontawesome-free/scss/_larger.scss 7:17     @import
    node_modules/@fortawesome/fontawesome-free/scss/fontawesome.scss 8:9  @import
    app/javascript/pay/style.scss 2:9                                     root stylesheet
DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div($fa-li-width * 5, 4) or calc($fa-li-width * 5 / 4)
More info and automated migrator: https://sass-lang.com/d/slash-div
  ╷
6 │   margin-left: $fa-li-width * 5/4;
  │                ^^^^^^^^^^^^^^^^^^
  ╵
    node_modules/@fortawesome/fontawesome-free/scss/_list.scss 6:16        @import
    node_modules/@fortawesome/fontawesome-free/scss/fontawesome.scss 10:9  @import
    app/javascript/pay/style.scss 2:9                                      root stylesheet
DEPRECATION WARNING: Using / for division outside of calc() is deprecated and will be removed in Dart Sass 2.0.0.
Recommendation: math.div($spacer, 2) or calc($spacer / 2)
More info and automated migrator: https://sass-lang.com/d/slash-div
    ╷
298 │ $headings-margin-bottom:      $spacer / 2 !default;
    │                               ^^^^^^^^^^^
    ╵
    node_modules/bootstrap/scss/_variables.scss 298:31  @import
    node_modules/bootstrap/scss/bootstrap.scss 9:9      @import
    app/javascript/pay/style.scss 5:9                   root stylesheet
WARNING: 62 repetitive deprecation warnings omitted.

[armahillo]

https://sass-lang.com/documentation/breaking-changes/slash-div