pass input for what to test field on testflight

.github/workflows/build-submit-ios.yml

@@ -18,6 +18,11 @@ on:
           - QA Team
           - Software Mansion
         default: none
+      changelog:
+        type: string
+        description: TestFlight "What to Test" notes (only applied when a group is selected)
+        required: false
+        default: ''
   workflow_call:
     inputs:
       profile:
@@ -270,6 +275,7 @@ jobs:
       - name: 🧪 Assign build to TestFlight group
         env:
           TESTFLIGHT_GROUP: ${{ inputs.testFlightGroup }}
+          CHANGELOG: ${{ inputs.changelog }}
           ASC_KEY_ID: ${{ secrets.ASC_KEY_ID }}
           ASC_ISSUER_ID: ${{ secrets.ASC_ISSUER_ID }}
           ASC_KEY_P8_BASE64: ${{ secrets.ASC_KEY_P8_BASE64 }}
@@ -288,6 +294,12 @@ jobs:
             --arg key "$key_content" \
             '{key_id: $key_id, issuer_id: $issuer_id, key: $key, in_house: false}' \
             > asc_api_key.json
+          # changelog is optional, and passing it empty would blank out whatever "What to
+          # Test" notes the build already has, so only include the flag when it is set.
+          changelog_arg=()
+          if [ -n "$CHANGELOG" ]; then
+            changelog_arg=(changelog:"$CHANGELOG")
+          fi
           # app_platform is required in non-interactive mode: distribute_only otherwise
           # calls fetch_app_platform, which prompts for input and crashes without a TTY.
           fastlane run upload_to_testflight \
@@ -298,4 +310,5 @@ jobs:
             app_version:"$APP_VERSION" \
             build_number:"$BUILD_NUMBER" \
             groups:"$TESTFLIGHT_GROUP" \
-            notify_external_testers:true
+            notify_external_testers:true \
+            "${changelog_arg[@]}"