Updated bg-transparent-subdued value (#9784)

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### WHY are these changes introduced?

Fixes Shopify/archive-polaris-backlog-2024#997

### WHAT is this pull request doing?

This PR updates bg-transparent-subdued value to increase contrast of
default badges

<img width="841" alt="image"
src="https://github.com/Shopify/polaris/assets/8629173/3ae74bea-b493-45b4-bf0f-d92656c523a4">

polaris-tokens/src/token-groups/color.ts

@@ -940,7 +940,7 @@ export const color: {
     description: '',
   },
   'color-bg-transparent-subdued-experimental': {
-    value: colorsExperimental.gray[16]('0.05'),
+    value: colorsExperimental.gray[16]('0.07'),
     description: '',
   },
   'color-bg-transparent-hover-experimental': {