Bump serde_yaml from 0.8.20 to 0.8.21 (#115)

Bumps [serde_yaml](https://github.com/dtolnay/serde-yaml) from 0.8.20 to 0.8.21.
- [Release notes](https://github.com/dtolnay/serde-yaml/releases)
- [Commits](https://github.com/dtolnay/serde-yaml/compare/0.8.20...0.8.21)

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

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Dave G <dave.gallant@rewind.io>

Cargo.lock

@@ -917,9 +917,9 @@ dependencies = [
 
 [[package]]
 name = "serde_yaml"
-version = "0.8.20"
+version = "0.8.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ad104641f3c958dab30eb3010e834c2622d1f3f4c530fef1dee20ad9485f3c09"
+checksum = "d8c608a35705a5d3cdc9fbe403147647ff34b921f8e833e49306df898f9b20af"
 dependencies = [
  "dtoa",
  "indexmap",