Run Rust CI when Cargo.lock changes too (#14571)

* Run Rust CI when Cargo.lock changes too

* Changelog

.github/workflows/tests.yml

@@ -27,6 +27,7 @@ jobs:
           rust:
             - 'rust/**'
             - 'Cargo.toml'
+            - 'Cargo.lock'
 
   check-sampleconfig:
     runs-on: ubuntu-latest

changelog.d/14571.misc

+Run Rust CI when `Cargo.lock` changes. This is particularly useful for dependabot updates.