dataconnect: demo: make codegen gradle task cacheable

[dconeybe]

firebase-dataconnect/demo/build.gradle.kts: make DataConnectGenerateSourcesTask cacheable to demonstrate making a task cacheable, and, in theory, could speed up incremental builds.

[github-actions]

Release note changes

No release note changes were detected. If you made changes that should be
present in the next release, ensure you've added an entry in the appropriate
CHANGELOG.md file(s).

[github-actions]

📝 PRs merging into main branch

Our main branch should always be in a releasable state. If you are working on a larger change, or if you don't want this change to see the light of the day just yet, consider using a feature branch first, and only merge into the main branch when the code complete and ready to be released.

[github-actions]

Vertex AI Mock Responses Check ⚠️

A newer major version of the mock responses for Vertex AI unit tests is available. update_responses.sh should be updated to clone the latest version of the responses: v5.2

[google-oss-bot]

Coverage Report ¹

Affected Products

No changes between base commit (11403df) and merge commit (75b8206).

Test Logs

• Base (11403df): https://github.com/firebase/firebase-android-sdk/actions/runs/12205775180
• Merge (75b8206): https://github.com/firebase/firebase-android-sdk/actions/runs/12206666627

1. https://storage.googleapis.com/firebase-sdk-metric-reports/vCvB8P0Gki.html

[google-oss-bot]

Size Report ¹

Affected Products

No changes between base commit (11403df) and merge commit (75b8206).

Test Logs

• Base (11403df): https://github.com/firebase/firebase-android-sdk/actions/runs/12205775180
• Merge (75b8206): https://github.com/firebase/firebase-android-sdk/actions/runs/12206666627

1. https://storage.googleapis.com/firebase-sdk-metric-reports/FHmHFXEUH9.html

[github-actions]

Test Results

   62 files   -    974     62 suites   - 974   1m 13s ⏱️ - 31m 39s
  541 tests  -  5 332    540 ✅  -  5 311  1 💤  - 21  0 ❌ ±0 
1 082 runs   - 10 749  1 080 ✅  - 10 707  2 💤  - 42  0 ❌ ±0 

Results for commit 8987469. ± Comparison against base commit 11403df.

This pull request removes 5332 tests.

com.google.android.datatransport.cct.CctBackendFactoryTest ‑ create_returnCCTBackend_WhenBackendNameIsCCT
com.google.android.datatransport.cct.CctDestinationTest ‑ cctDestination_shouldOnlySupportProtoAndJson
com.google.android.datatransport.cct.CctDestinationTest ‑ cctDestination_shouldSupportProtoAndJson
com.google.android.datatransport.cct.CctTransportBackendTest ‑ decorate_whenOffline_shouldProperlyPopulateNetworkInfo
com.google.android.datatransport.cct.CctTransportBackendTest ‑ decorate_whenOnline_shouldProperlyPopulateNetworkInfo
com.google.android.datatransport.cct.CctTransportBackendTest ‑ schedule_shouldAddCookieOnPseudonymousIds
com.google.android.datatransport.cct.CctTransportBackendTest ‑ schedule_shouldDropCookieOnMixedPseudonymousIds
com.google.android.datatransport.cct.CctTransportBackendTest ‑ send_CompressedResponseIsUncompressed
com.google.android.datatransport.cct.CctTransportBackendTest ‑ send_whenBackendRedirectsMoreThan5Times_shouldOnlyRedirect4Times
com.google.android.datatransport.cct.CctTransportBackendTest ‑ send_whenBackendRedirects_shouldCorrectlyFollowTheRedirectViaPost
…

♻️ This comment has been updated with latest results.