remove concurrency on workflow_call github workflows

[modular-magician]

https://github.com/GoogleCloudPlatform/magic-modules/actions/runs/13204479522/job/36864303644?pr=12992

• The called workflow using workflow_call should inherit the full event payload from the calling workflow, including github.event.pull_request context
• However, we're seeing the PR number missing from concurrency group names, suggesting this inheritance isn't working as expected
• Added debug steps to inspect the available context in the called workflow
• Switching to using github.event.number For whatever reason github.event.pull_request.number is sometimes missing.

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Derived from GoogleCloudPlatform/magic-modules#12998