[RadioButton]: make onChange optional

[AlanBreck]

When in a Svelte consumer, sometimes it's easiest to use the bind:value technique instead of an onChange handler.

[github-actions]

👋 Thanks for Submitting! This PR is available for preview at the link below.

✅ PR tip preview: https://825.pr.nala.bravesoftware.com/
✅ Commit preview: https://825.pr.nala.bravesoftware.com/commit-2cba6ab5b80ee2a82b03f33cdb1a76151278681d/

- ./tokens/css/variables-android.old.css: 7424 bytes
+ ./tokens/css/variables-android.css: 7424 bytes
---
- ./tokens/css/variables-browser.old.css: 6874 bytes
+ ./tokens/css/variables-browser.css: 6874 bytes
---
- ./tokens/css/variables-ios.old.css: 7067 bytes
+ ./tokens/css/variables-ios.css: 7067 bytes
---
- ./tokens/css/variables-marketing.old.css: 13561 bytes
+ ./tokens/css/variables-marketing.css: 13561 bytes
---
- ./tokens/css/variables-news.old.css: 526 bytes
+ ./tokens/css/variables-news.css: 526 bytes
---
- ./tokens/css/variables-newtab.old.css: 1941 bytes
+ ./tokens/css/variables-newtab.css: 1941 bytes
---
- ./tokens/css/variables-search.old.css: 2419 bytes
+ ./tokens/css/variables-search.css: 2419 bytes
---
- ./tokens/css/variables-web3.old.css: 905 bytes
+ ./tokens/css/variables-web3.css: 905 bytes
---
- ./tokens/css/variables.old.css: 114834 bytes
+ ./tokens/css/variables.css: 114834 bytes

Variables Diff: variables-android.diff

--- ./tokens/css/variables-android.old.css	2024-09-12 15:06:33.381273876 +0000
+++ ./tokens/css/variables-android.css	2024-09-12 15:05:54.740699444 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Sep 11 2024 14:47:24 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Sep 12 2024 15:05:54 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-browser.diff

--- ./tokens/css/variables-browser.old.css	2024-09-12 15:06:33.769279911 +0000
+++ ./tokens/css/variables-browser.css	2024-09-12 15:05:54.724699181 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Sep 11 2024 14:47:24 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Sep 12 2024 15:05:54 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-ios.diff

--- ./tokens/css/variables-ios.old.css	2024-09-12 15:06:34.137285631 +0000
+++ ./tokens/css/variables-ios.css	2024-09-12 15:05:54.760699773 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Sep 11 2024 14:47:24 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Sep 12 2024 15:05:54 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-marketing.diff

--- ./tokens/css/variables-marketing.old.css	2024-09-12 15:06:34.537291864 +0000
+++ ./tokens/css/variables-marketing.css	2024-09-12 15:05:54.784700169 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Sep 11 2024 14:47:24 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Sep 12 2024 15:05:54 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-news.diff

--- ./tokens/css/variables-news.old.css	2024-09-12 15:06:34.925297896 +0000
+++ ./tokens/css/variables-news.css	2024-09-12 15:05:54.808700565 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Sep 11 2024 14:47:24 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Sep 12 2024 15:05:54 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-newtab.diff

--- ./tokens/css/variables-newtab.old.css	2024-09-12 15:06:35.309303869 +0000
+++ ./tokens/css/variables-newtab.css	2024-09-12 15:05:54.816700697 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Sep 11 2024 14:47:24 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Sep 12 2024 15:05:54 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-search.diff

--- ./tokens/css/variables-search.old.css	2024-09-12 15:06:35.669309469 +0000
+++ ./tokens/css/variables-search.css	2024-09-12 15:05:54.800700433 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Sep 11 2024 14:47:24 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Sep 12 2024 15:05:54 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {

Variables Diff: variables-web3.diff

--- ./tokens/css/variables-web3.old.css	2024-09-12 15:06:36.065315633 +0000
+++ ./tokens/css/variables-web3.css	2024-09-12 15:05:54.824700828 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Sep 11 2024 14:47:24 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Sep 12 2024 15:05:54 GMT+0000 (Coordinated Universal Time)
  */
 
 @media (prefers-color-scheme: light) {

Variables Diff: variables.diff

--- ./tokens/css/variables.old.css	2024-09-12 15:06:36.725325901 +0000
+++ ./tokens/css/variables.css	2024-09-12 15:05:54.580696806 +0000
@@ -1,6 +1,6 @@
 /**
  * Do not edit directly
- * Generated on Wed Sep 11 2024 14:47:24 GMT+0000 (Coordinated Universal Time)
+ * Generated on Thu Sep 12 2024 15:05:54 GMT+0000 (Coordinated Universal Time)
  */
 
 :root {