deduplicate running jobs on BigQueryInsertJobOperator

[blcksrx]

The job.result method already invokes on the hook.insert_job method, so basically it's duplicated beside of the referenced issue.

airflow/airflow/providers/google/cloud/hooks/bigquery.py

Lines 1639 to 1641 in ef1b124

	# Start the job and wait for it to complete and get the result.
	job.result()
	return job

In addition, In my opinion, the insert_job method should only responsible to inserting a job not verifying the job is completed and wait for it.

---

related: #17493

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

[kaxil]

Following test is failing, can you fix it please @blcksrx

  FAILED tests/providers/google/cloud/operators/test_bigquery.py::TestBigQueryInsertJobOperator::test_execute_reattach

https://github.com/apache/airflow/pull/17496/checks?check_run_id=3275336377#step:6:7406

[blcksrx]

@kaxil Thanks for noticing, it was an stupid error on unit-test side, I fixed it but unfortunately CI failed because of some conflict in installing packages that is unrelated to this PR.

[eladkal]

@blcksrx can you please rebase - it will probably solve the CI problems

[blcksrx]

@eladkal Thanks man