build(deps): bump solana-program-pack from 3.0.0 to 3.1.0 (#580)

Bumps [solana-program-pack](https://github.com/anza-xyz/solana-sdk) from 3.0.0 to 3.1.0.
- [Release notes](https://github.com/anza-xyz/solana-sdk/releases)
- [Commits](https://github.com/anza-xyz/solana-sdk/compare/sdk@v3.0.0...msg@v3.1.0)

---
updated-dependencies:
- dependency-name: solana-program-pack
  dependency-version: 3.1.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Cargo.lock

@@ -30,7 +30,7 @@ solana-msg = "3.0.0"
 solana-program-entrypoint = "3.0.0"
 solana-program-error = "3.0.0"
 solana-program-memory = "3.0.0"
-solana-program-pack = "3.0.0"
+solana-program-pack = "3.1.0"
 solana-pubkey = { version = "4.1.0", features = ["curve25519"] }
 solana-rent = "4.0.0"
 solana-sdk-ids = "3.1.0"