chore(ci): Migrate smp regression workflow auth from static secrets to oidc

[cmetz100]

Summary

Migrate authentication for the regression suite (SMP) from static secrets to oidc

Vector configuration

How did you test this PR?

Change Type

• Bug fix
• New feature
• Dependencies
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the no-changelog label to this PR.

References

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[pront]

Thanks @cmetz100, this is a nice improvement!