chore(deps): bump mockall from 0.14.0 to 0.15.0

Bumps [mockall](https://github.com/asomers/mockall) from 0.14.0 to 0.15.0.
- [Changelog](https://github.com/asomers/mockall/blob/master/CHANGELOG.md)
- [Commits](asomers/mockall@v0.14.0...v0.15.0)

---
updated-dependencies:
- dependency-name: mockall
  dependency-version: 0.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

Cargo.lock

@@ -104,7 +104,7 @@ path = "src/bin/kata_config_agent.rs"
 
 [dev-dependencies]
 tokio-test = "0.4"
-mockall = "0.14"
+mockall = "0.15"
 test-log = "0.2"
 tempfile = "3"
 tower-test = "0.4"