Bump diesel from 2.2.0 to 2.2.1 in /examples (#395)

Bumps [diesel](https://github.com/diesel-rs/diesel) from 2.2.0 to 2.2.1.
- [Release notes](https://github.com/diesel-rs/diesel/releases)
- [Changelog](https://github.com/diesel-rs/diesel/blob/v2.2.1/CHANGELOG.md)
- [Commits](https://github.com/diesel-rs/diesel/compare/v2.2.0...v2.2.1)

---
updated-dependencies:
- dependency-name: diesel
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

examples/Cargo.lock

@@ -992,9 +992,9 @@ dependencies = [
 
 [[package]]
 name = "diesel"
-version = "2.2.0"
+version = "2.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "35b696af9ff4c0d2a507db2c5faafa8aa0205e297e5f11e203a24226d5355e7a"
+checksum = "62d6dcd069e7b5fe49a302411f759d4cf1cf2c27fe798ef46fb8baefc053dd2b"
 dependencies = [
  "diesel_derives",
  "libsqlite3-sys",