Fix iOS integration tests failing to build due to bitcode (#503)

* Pin xcode version

* Update integration_tests.yml

Author: a-maurice

.github/workflows/integration_tests.yml

@@ -169,6 +169,8 @@ jobs:
       U3D_PASSWORD: ""
       # Disable checking for U3D updates, since it is buggy
       U3D_SKIP_UPDATE_CHECK: 1
+      # Which xcode version to use
+      xcodeVersion: "13.3.1"
     steps:
       - id: matrix_info
         run: |
@@ -194,6 +196,9 @@ jobs:
         shell: bash
         run: |
           pip install -r scripts/gha/requirements.txt
+      - name: setup Xcode version
+        if: runner.os == 'macOS'
+        run: sudo xcode-select -s /Applications/Xcode_${{ env.xcodeVersion }}.app/Contents/Developer
       - name: Install Unity
         uses: nick-invision/retry@v2
         with: