Bump anchor-syn from 0.24.2 to 0.28.0

Bumps [anchor-syn](https://github.com/coral-xyz/anchor) from 0.24.2 to 0.28.0.
- [Release notes](https://github.com/coral-xyz/anchor/releases)
- [Changelog](https://github.com/coral-xyz/anchor/blob/master/CHANGELOG.md)
- [Commits](solana-foundation/anchor@v0.24.2...v0.28.0)

---
updated-dependencies:
- dependency-name: anchor-syn
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Cargo.lock

@@ -12,7 +12,7 @@ keywords = ["solana", "anchor"]
 compat-program-result = []
 
 [dependencies]
-anchor-syn = { version = "0.24.2", features = ["idl"] }
+anchor-syn = { version = "0.28.0", features = ["idl"] }
 darling = "0.14"
 heck = "0.4.1"
 proc-macro2 = "1"