[FLINK-40720][ci] Checkout only current branch in Azure

[snuyanzin]

What is the purpose of the change

The PR to make checkouting only current branch instead of all

Brief change log

azure

Verifying this change

azure ci

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): (no)
• The public API, i.e., is any changed class annotated with @Public(Evolving): (no)
• The serializers: (no)
• The runtime per-record code paths (performance sensitive): (no)
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: (no)
• The S3 file system connector: (no)

Documentation

• Does this pull request introduce a new feature? (no)
• If yes, how is the feature documented? (not applicable)

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• Yes (please specify the tool below)

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[flinkbot]

CI report:

• c46c29f Azure: SUCCESS

Bot commands

The @flinkbot bot supports the following commands:

• @flinkbot run azure re-run the last Azure build

[spuru9]

docs_404_check still uses the default checkout (full ~10k-branch fetch from the flink-ci/flink mirror) on every PR — should it get the single-branch template too?
https://dev.azure.com/apache-flink/apache-flink/_build/results?buildId=79263&view=logs&j=c5d67f7d-375d-5407-4743-f9d0c4436a81&t=590246b1-2ba8-52a2-ec20-918a70232be9

[snuyanzin]

yeah, good catch
thanks, fixed

[snuyanzin]

@spuru9 are you happy with current changes?

[spuru9]

@spuru9 are you happy with current changes?

Yes Thanks Down to 1, https://dev.azure.com/apache-flink/apache-flink/_build/results?buildId=79295&view=logs&j=c5d67f7d-375d-5407-4743-f9d0c4436a81&t=c368f5c0-9856-504c-e459-25e869238f70

[spuru9]

LGTM