chore: Fixing retries in unit tests workflow (#3293)

Author: sebaland

.github/workflows/run_xcodebuild_test_platforms.yml

@@ -98,7 +98,8 @@ jobs:
           cloned_source_packages_path: ~/Library/Developer/Xcode/DerivedData/Amplify
           derived_data_path: ${{ github.workspace }}/Build
           disable_package_resolution: true
-          test_without_building: true
+          # Only test without building when this exact SHA was cached or we did not restore the build from main.
+          test_without_building: ${{ steps.restore-build.outputs.cache-hit || !steps.restore-main-build.outputs.cache-hit }}
           other_flags: ${{ inputs.other_flags }}
       - name: Save the SHA build cache for re-runs
         if: failure() && steps.retry-tests.outcome=='failure'
@@ -201,7 +202,8 @@ jobs:
           cloned_source_packages_path: ~/Library/Developer/Xcode/DerivedData/Amplify
           derived_data_path: ${{ github.workspace }}/Build
           disable_package_resolution: true
-          test_without_building: true
+          # Only test without building when this exact SHA was cached or we did not restore the build from main.
+          test_without_building: ${{ steps.restore-build.outputs.cache-hit || !steps.restore-main-build.outputs.cache-hit }}
           other_flags: ${{ inputs.other_flags }}
       - name: Save the SHA build cache for re-runs
         if: failure() && steps.retry-tests.outcome=='failure'
@@ -295,7 +297,8 @@ jobs:
           cloned_source_packages_path: ~/Library/Developer/Xcode/DerivedData/Amplify
           derived_data_path: ${{ github.workspace }}/Build
           disable_package_resolution: true
-          test_without_building: true
+          # Only test without building when this exact SHA was cached or we did not restore the build from main.
+          test_without_building: ${{ steps.restore-build.outputs.cache-hit || !steps.restore-main-build.outputs.cache-hit }}
           other_flags: ${{ inputs.other_flags }}
       - name: Save the SHA build cache for re-runs
         if: failure() && steps.retry-tests.outcome=='failure'
@@ -389,7 +392,8 @@ jobs:
           cloned_source_packages_path: ~/Library/Developer/Xcode/DerivedData/Amplify
           derived_data_path: ${{ github.workspace }}/Build
           disable_package_resolution: true
-          test_without_building: true
+          # Only test without building when this exact SHA was cached or we did not restore the build from main.
+          test_without_building: ${{ steps.restore-build.outputs.cache-hit || !steps.restore-main-build.outputs.cache-hit }}
           other_flags: ${{ inputs.other_flags }}
       - name: Save the SHA build cache for re-runs
         if: failure() && steps.retry-tests.outcome=='failure'