[Failing Test]: Re-enable the skipped Change Stream Unit tests after refactor test code

[jiangzzhu]

What happened?

Re-enable the following temporary disabled unit tests.

SpannerChangeStreamErrorTest > testResourceExhaustedRetry FAILED java.lang.AssertionError at MatcherAssert.java:18

SpannerChangeStreamErrorTest > testInvalidRecordReceived FAILED java.lang.AssertionError at MatcherAssert.java:18

SpannerChangeStreamErrorTest > testUnavailableExceptionRetries FAILED java.lang.AssertionError at MatcherAssert.java:18

SpannerChangeStreamErrorTest > testAbortedExceptionRetries FAILED java.lang.AssertionError at MatcherAssert.java:18

Issue Failure

Failure: Test is flaky

Issue Priority

Priority: 1 (unhealthy code / failing or flaky postcommit so we cannot be sure the product is healthy)

Issue Components

• [ ] Component: Python SDK
• [ ] Component: Java SDK
• [ ] Component: Go SDK
• [ ] Component: Typescript SDK
• [ ] Component: IO connector
• [ ] Component: Beam YAML
• [ ] Component: Beam examples
• [ ] Component: Beam playground
• [ ] Component: Beam katas
• [ ] Component: Website
• [ ] Component: Infrastructure
• [ ] Component: Spark Runner
• [ ] Component: Flink Runner
• [ ] Component: Samza Runner
• [ ] Component: Twister2 Runner
• [ ] Component: Hazelcast Jet Runner
• [ ] Component: Google Cloud Dataflow Runner