[BEAM-11088] TestStream utility and testing improvements

[jrmccluskey]

Adds an AddElementList() function to the TestStream config object, allowing users to add slices/arrays to the stream object at once. Also fleshes out the integration test suite for TestStream to test multiple input types (int64, float 64, bool) and adds comments indicating that these are the three currently supported types.

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ValidatesRunner compliance status (on master branch)

Lang	ULR	Dataflow	Flink	Samza	Spark	Twister2
Go	---					---
Java
Python	---					---
XLang						---

Examples testing status on various runners

Lang	ULR	Dataflow	Flink	Samza	Spark	Twister2
Go	---	---	---	---	---	---	---
Java	---		---	---	---	---	---
Python	---	---	---	---	---	---	---
XLang	---	---	---	---	---	---	---

Post-Commit SDK/Transform Integration Tests Status (on master branch)

Go	Java	Python

Pre-Commit Tests Status (on master branch)

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

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

GitHub Actions Tests Status (on master branch)

See CI.md for more information about GitHub Actions CI.

[jrmccluskey]

Run Go PostCommit

[jrmccluskey]

Run Go Flink ValidatesRunner

[jrmccluskey]

R: @lostluck

[lostluck]

Thanks!

[lostluck]

It appears that we've finally overloaded our little jenkins server with running all the integration tests packages simultaneously. I have PR #15321 to constrain that a bit, and once merged, we'll re run and see if that fixes it.

[lostluck]

Run Go Flink ValidatesRunner

[lostluck]

Run Go PostCommit

[jrmccluskey]

Run Go PostCommit

[jrmccluskey]

Run Go Flink ValidatesRunner

[jrmccluskey]

Run Go Flink ValidatesRunner

[jrmccluskey]

Run Go PostCommit

[jrmccluskey]

Run Go Flink ValidatesRunner

[jrmccluskey]

Run Go PostCommit

[jrmccluskey]

Run Go Flink ValidatesRunner

[jrmccluskey]

Run Go Flink ValidatesRunner

[jrmccluskey]

Run Go PostCommit

[lostluck]

Well that one's weird. It can't find the Go SDK container? don't know why that's happening. AFAICT it built it, but it's not being found by Flink... Hmmm.

[jrmccluskey]

Run Go PostCommit

[jrmccluskey]

Run Go Flink ValidatesRunner

[lostluck]

I'm going to merge this in, understanding that the new tests aren't enabled right now. Easier to investigate then too. Thanks!