Bump io.mockk:mockk from 1.10.2 to 1.13.8

Bumps [io.mockk:mockk](https://github.com/mockk/mockk) from 1.10.2 to 1.13.8.
- [Release notes](https://github.com/mockk/mockk/releases)
- [Commits](mockk/mockk@1.10.2...1.13.8)

---
updated-dependencies:
- dependency-name: io.mockk:mockk
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

build.gradle

@@ -35,7 +35,7 @@ buildscript {
         androidxTestCoreVersion = '1.3.0'
         junitGradlePluignVersion = '1.6.1.0'
         junitVersion = '5.5.2'
-        mockkVersion = '1.10.2'
+        mockkVersion = '1.13.8'
         robolectricVersion = '4.4'
         truthVersion = '1.1'
         vintageJunitVersion = '4.12'