chore(deps): update dependency yamlfmt to v0.21.0 (#93)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

mise.toml

@@ -2,4 +2,4 @@
 python = "3.13"
 uv = "latest"
 just = "latest"
-yamlfmt = "0.17.2"
+yamlfmt = "0.21.0"