fix: log deprecated bearer token fields at debug level

[simonpasquier]

Description

Closes #6493

Type of change

What type of changes does your code introduce to the Prometheus operator? Put an x in the box that apply.

• CHANGE (fix or feature that would cause existing functionality to not work as expected)
• FEATURE (non-breaking change which adds functionality)
• BUGFIX (non-breaking change which fixes an issue)
• ENHANCEMENT (non-breaking change which improves existing functionality)
• NONE (if none of the other choices apply. Example, tooling, build system, CI, docs, etc.)

Verification

Please check the Prometheus-Operator testing guidelines for recommendations about automated tests.

Changelog entry

Please put a one-line changelog entry below. This will be copied to the changelog file during the release process.

[juzhao]

@simonpasquier do we need to change for
level.Warn(cg.logger).Log("msg", "'bearerToken' is deprecated, use 'authorization' instead.")
there are 3 such warnings in 0.73.0, example:
https://github.com/prometheus-operator/prometheus-operator/blob/release-0.73/pkg/prometheus/promcfg.go#L1740

[slashpai]

we missed here as Junqi said

prometheus-operator/pkg/prometheus/promcfg.go

Line 1740 in 36f01b5

level.Warn(cg.logger).Log("msg", "'bearerToken' is deprecated, use 'authorization' instead.")

[simonpasquier]

I left them because these fields are both deprecated and not recommended for use because they expose the tokens directly in the Prometheus object.

[slashpai]

Should we add more details why it was deprecated or may be in docs?