feat(guard): get tracker support string array

[MonveChen]

PR Checklist

Please check if your PR fulfills the following requirements:

• [x] The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• [x] Tests for the changes have been added (for bug fixes / features)
• [x] Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• [ ] Bugfix
• [x] Feature
• [ ] Code style update (formatting, local variables)
• [ ] Refactoring (no functional changes, no api changes)
• [ ] Build related changes
• [ ] CI related changes
• [ ] Other... Please describe:

What is the current behavior?

Multiple strings, such as req.ips or user identity, need to be restricted. And because req.ips[0] can be faked, all req.ips should be restricted

What is the new behavior?

Compatible with limiting multiple strings

Does this PR introduce a breaking change?

• [ ] Yes
• [x] No

Other information

[MonveChen]

Code looks good overall. Sorry for taking so long to getting to a review. Can you also add a changeset for this as a minor bump? Just run yarn changeset and follow the wizard

sure.