Adding EdgeModifier support for chain()

[josh-fell]

Closes: #17083

• Added support for EdgeModifier in chain() helper function
• Added additional tests in test_baseoperator.py

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[github-actions]

The PR most likely needs to run full matrix of tests because it modifies parts of the core of Airflow. However, committers might decide to merge it quickly and take the risk. If they don't merge it quickly - please rebase it to the latest main at your convenience, or amend the last commit of the PR, and push it with --force-with-lease.

[github-actions]

The PR most likely needs to run full matrix of tests because it modifies parts of the core of Airflow. However, committers might decide to merge it quickly and take the risk. If they don't merge it quickly - please rebase it to the latest main at your convenience, or amend the last commit of the PR, and push it with --force-with-lease.

[kaxil]

Tests are failing @josh-fell

[josh-fell]

Tests are failing @josh-fell

Some of these failures look to be resource-related. Rebasing and let's see how the new test runs turn out.

[josh-fell]

@kaxil Not as many failures after the rebase.

The 4 failing MSSQL tests are failing for the same reason in this issue comment.

The failing Postgres and MySQL jobs pass locally for the offending test "test_scheduler_job.py":
./breeze --python 3.9 --backend postgres --postgres-version 13 tests tests/jobs/test_scheduler_job.py

./breeze --python 3.6 --backend mysql --mysql-version 5.7 tests tests/jobs/test_scheduler_job.py

How should I proceed?

[potiuk]

Looks like transient errors only. Merging