ci: relocate license check to prevent blocking other CI jobs

[alan-agius4]

Relocates the "Check Package Licenses" step in pr.yml to ensure that failures in this specific check do not prevent other critical CI jobs from completing or providing feedback on pull requests.

[dgp1130]

This PR was merged into the repository. The changes were merged into the following branches:

• main: 89f9c8a
• 21.0.x: 4187d46

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