feat(secret): license the secret management feature

[yuhao-su]

I hereby agree to the terms of the RisingWave Labs, Inc. Contributor License Agreement.

What's changed and what's your intention?

Require paid tier for secret management feature. Only disallow create/drop secret when unlicensed.

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added test labels as necessary. See details.
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

• My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.

[BugenZhao]

Shall we also check the license when using (inlining) an existing secret?

[yuhao-su]

Shall we also check the license when using (inlining) an existing secret?

We can. It really depends on what error message we want to show.

Also should we allow users to use secrets created when they are licensed and just disallow any creating new secrets? cc @neverchanje

---

After some discussion, we decide to only disallow unlicensed user create/drop secret.