[ARROW-14587] [CI][Crossbow] Fetch a single crossbow branch instead of the full repo on Azure

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: Continuous Integration
• External issue URL: https://github.com/apache/arrow/issues/30135
• Assignee: Unassigned
• Reporter: Krisztian Szucs
• Created: 04/Nov/21 13:53
• Updated: 11/Jan/23 08:40

Description

Since crossbow has a lot of references the checkout step can take a long time, see build https://dev.azure.com/ursacomputing/crossbow/_build/results?buildId=14952&view=logs&j=0da5d1d9-276d-5173-c4c4-9d4d4ed14fdb&t=5bbb8710-d4c1-5a8b-fc80-a388730cf6ac

We should alter the azure crossbow template to explicitly check out the task's branch using
{{ {{ task.branch }} }} jinja variable.

See azure documentation: https://docs.microsoft.com/en-us/azure/devops/pipelines/repos/multi-repo-checkout?view=azure-devops#checking-out-a-specific-ref