build(deps): bump golang.org/x/tools from 0.20.0 to 0.21.0

Bumps [golang.org/x/tools](https://github.com/golang/tools) from 0.20.0 to 0.21.0.
- [Release notes](https://github.com/golang/tools/releases)
- [Commits](https://github.com/golang/tools/compare/v0.20.0...v0.21.0)

---
updated-dependencies:
- dependency-name: golang.org/x/tools
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

go.mod

@@ -9,7 +9,7 @@ require (
 	github.com/goplus/mod v0.13.10
 	github.com/json-iterator/go v1.1.12
 	github.com/qiniu/x v1.13.10
-	golang.org/x/tools v0.20.0
+	golang.org/x/tools v0.21.0
 )
 
 require (