chore(ci): remove pinned actions & pkg versions

[dreamorosi]

Summary

Changes

Please provide a summary of what's being changed

This PR updates the bootstrap_region.yml workflow with three changes:

• The copy_layers step is now dependant on the bootstrap one
• The bootstrap step checks out the repo and uses the CDK version present - this avoids pinning the CDK version
• The copy_layers step uses a specific version of the shared action identified by its commit hash, rather than the latest one

Please add the issue number below, if no issue is present the PR might get blocked and not be reviewed

Issue number: closes #3573

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[leandrodamascena]

Please check my comments.

[dreamorosi]

Removed the content: write from both jobs, thank you for noticing!

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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