license: unredact logs written by license enforcer

[rafiss]

This makes it so log messages are not redacted unnecessarily.

• Use redact.StringBuilder instead of strings.Builder.
• Avoid using .String() arguments for log.Infof, since strings are always redacted.
• Mark license type as a redact.SafeValue.

Epic: None
Release note: None

[blathers-crl]

It looks like your PR touches production code but doesn't add or edit any test code. Did you consider adding tests to your PR?

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is dev-inf.}

[cockroach-teamcity]

This change is 

[spilchen]

Your CI failures look related to the SafeValue change for LicType. Do we need to update the allowlist in redactcheck.go?

Reviewed 3 of 3 files at r1, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @rafiss)

[rafiss]

ah yeah, that's correct. i always forget about that redactcheck linter

[rafiss]

tftr!

bors r+

[craig]

Build succeeded:

• linux_arm64_build
• local_roachtest
• docker_image_amd64
• macos_amd64_build
• linux_amd64_fips_build
• macos_arm64_build
• linux_amd64_build
• windows_build
• acceptance
• check_generated_code
• examples_orms
• local_roachtest_fips
• lint
• unit_tests

[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

You might need to create your backport manually using the backport tool.

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error creating merge commit from 255f10f to blathers/backport-release-23.1-134875: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 23.1.x failed. See errors above.

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_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is dev-inf.}