Bump leakcanary-android from 2.7 to 2.8

Bumps [leakcanary-android](https://github.com/square/leakcanary) from 2.7 to 2.8.
- [Release notes](https://github.com/square/leakcanary/releases)
- [Changelog](https://github.com/square/leakcanary/blob/main/docs/changelog.md)
- [Commits](https://github.com/square/leakcanary/compare/v2.7...v2.8)

---
updated-dependencies:
- dependency-name: com.squareup.leakcanary:leakcanary-android
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

build.gradle

@@ -324,7 +324,7 @@ dependencies {
     }
 
     if (!ciBuild) {
-        debugImplementation 'com.squareup.leakcanary:leakcanary-android:2.7'
+        debugImplementation 'com.squareup.leakcanary:leakcanary-android:2.8'
     }
 
     // dependencies for local unit tests