[Infra] Run Auth QS with Xcode 16 to resolve Facebook SDK breaking change (#14129)

Author: ncooke3

.github/workflows/prerelease.yml

@@ -247,13 +247,15 @@ jobs:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       signin_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       bot_token_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@v1
     - name: Get token
       run: scripts/decrypt_gha_secret.sh scripts/gha-encrypted/prerelease-testing-token.txt.gpg \
           bot-access.txt "$bot_token_secret"
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.1.app/Contents/Developer
     - name: Setup testing repo and quickstart
       run: |
           botaccess=`cat bot-access.txt`

.github/workflows/release.yml

@@ -195,13 +195,15 @@ jobs:
       plist_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       signin_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
       bot_token_secret: ${{ secrets.GHASecretsGPGPassphrase1 }}
-    runs-on: macos-14
+    runs-on: macos-15
     steps:
     - uses: actions/checkout@v4
     - uses: ruby/setup-ruby@v1
     - name: Get token
       run: scripts/decrypt_gha_secret.sh scripts/gha-encrypted/release-testing-token.txt.gpg \
           bot-access.txt "$bot_token_secret"
+    - name: Xcode
+      run: sudo xcode-select -s /Applications/Xcode_16.1.app/Contents/Developer
     - name: Setup testing repo and quickstart
       run: |
           botaccess=`cat bot-access.txt`