perf: don't invalidate grid rows more than once

[ghiscoding]

• see this Slickgrid-Universal comment for more details

[stackblitz]

Run & review this pull request in StackBlitz Codeflow.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 6 lines in your changes missing coverage. Please review.

Project coverage is 21.56%. Comparing base (ec2a86e) to head (ec31714).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...slickgrid/src/custom-elements/aurelia-slickgrid.ts	0.00%	6 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1265      +/-   ##
==========================================
- Coverage   21.63%   21.56%   -0.06%     
==========================================
  Files           8        8              
  Lines         934      937       +3     
  Branches      346      324      -22     
==========================================
  Hits          202      202              
- Misses        732      735       +3     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.