[BEAM-8079] Move release Gradle build to a Jenkins job (Part - 1)

[markflyhigh]

Reuse existing Jenkins machine to verify release Gradle build can get rid of painful environment setup in verify_release_branch.sh. Make it to a Jenkins job can also remove the restriction of the platform. Originally, the environment setup is specific to Linux-like system.

This Jenkins job can be used by release manager to verify Gradle build against a release branch. To do so, release manager needs to create a test PR against release branch (instead of master).

TODO: Update verify_release_branch.sh to use script.config. And also release guide.

+R: @yifanzou

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Post-Commit Tests Status (on master branch)

Lang	SDK	Apex	Dataflow	Flink	Gearpump	Samza	Spark
Go		---	---		---	---
Java
Python		---			---	---
XLang	---	---	---		---	---	---

Pre-Commit Tests Status (on master branch)

---	Java	Python	Go	Website
Non-portable
Portable	---		---	---

See .test-infra/jenkins/README for trigger phrase, status and link of all Jenkins jobs.

[markflyhigh]

Run Seed Job

[markflyhigh]

Run Seed Job

[markflyhigh]

Run Release Gradle Build

[markflyhigh]

release_build job took longer than Jenkins timeout. So we may want to remove --no-parallel to make the build faster.

[markflyhigh]

Run Seed Job

[markflyhigh]

Run Release Gradle Build

[markflyhigh]

Java PreCommit failed due to irrelevant test failure.
Release_Build failed with known issue: https://issues.apache.org/jira/browse/BEAM-7789. They are not release blocker.

[markflyhigh]

Thank you. I'll go ahead and merge.