Update mockall requirement from 0.12 to 0.13

Updates the requirements on [mockall](https://github.com/asomers/mockall) to permit the latest version.
- [Changelog](https://github.com/asomers/mockall/blob/master/CHANGELOG.md)
- [Commits](https://github.com/asomers/mockall/commits)

---
updated-dependencies:
- dependency-name: mockall
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Cargo.toml

@@ -31,7 +31,7 @@ tracing = "0.1"
 
 [dev-dependencies]
 tokio = { version = "1", features = ["macros"] }
-mockall = "0.12"
+mockall = "0.13"
 httpmock = "0.7"
 rand = "0.8"