Add border radii to Tailwind config

What does this MR do and why?

Adds Tailwind configuration for border radii.

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How to set up and validate locally

CSS-in-Js diff

diff --git a/config/helpers/tailwind/css_in_js.js b/config/helpers/tailwind/css_in_js.js
index 9a0cf18dd877..774139cb3f7f 100644
--- a/config/helpers/tailwind/css_in_js.js
+++ b/config/helpers/tailwind/css_in_js.js
@@ -1,5 +1,5 @@
 /**
- * The following 463 definitions need to be migrated to Tailwind.
+ * The following 459 definitions need to be migrated to Tailwind.
  * Let's do this! 🚀
  */
 module.exports = {
@@ -92,13 +92,9 @@ module.exports = {
   '.border-bottom-0\\!': { 'border-bottom': '0 !important' },
   '.rounded-0': { 'border-radius': '0' },
   '.rounded-0\\!': { 'border-radius': '0 !important' },
-  '.rounded-6': { 'border-radius': '1.5rem' },
-  '.rounded-base': { 'border-radius': '0.25rem' },
   '.rounded-base\\!': { 'border-radius': '0.25rem !important' },
   '.rounded-full\\!': { 'border-radius': '50% !important' },
-  '.rounded-small': { 'border-radius': '0.125rem' },
   '.rounded-lg\\!': { 'border-radius': '0.5rem !important' },
-  '.rounded-pill': { 'border-radius': '0.75rem' },
   '.rounded-left-none\\!': {
     'border-top-left-radius': '0 !important',
     'border-bottom-left-radius': '0 !important',

Related to #456620 (closed)