Remove failing tests from Nomulus GCB pipeline

Also upgrade to Gradle 5.4.1.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=246829399

release/cloudbuild-nomulus.yaml

@@ -26,7 +26,7 @@ steps:
   args: ['mkdir', 'nomulus']
 # Run tests
 - name: 'gcr.io/${PROJECT_ID}/builder:latest'
-  args: ['./gradlew', 'test']
+  args: ['./gradlew', 'test', '-PskipDockerIncompatibleTests=true']
   dir: 'gradle'
 # Build and package the deployment files for alpha.
 - name: 'gcr.io/${PROJECT_ID}/builder:latest'