feat: Add Jacoco coverage and report generation

[albendz]

Contributor checklist

• This pull request is on a separate branch and not the main branch
• [N/A] I have tested my code with the ./gradlew lintKotlin detekt test command as directed in the testing section of the contributing guide
• I have tested my code (see test notes below)

---

Description

This change adds the Jacoco plugin to the app/gradle.build.kts file with configuration to generate coverage reports.

Additionally, this adds a step to the unit test Github workflow to use the generated coverage XML to create a comment on PRs. This is not configured to fail the PR build. Details: https://github.com/marketplace/actions/jacoco-report

One thing I wasn't able to configure is coverage verification checks and build time.

I followed details provided in this Medium article on adding coverage to Android projects: https://medium.com/@nachare.reena8/measure-your-codes-reach-integrating-jacoco-code-coverage-in-android-apps-with-kotlin-dsl-382d577864e7

Testing

./gradlew tasks output:

Reporting tasks
---------------
jacocoCoreDebugCodeCoverage - Generate Jacoco coverage reports for the CoreDebug build
jacocoCoreReleaseCodeCoverage - Generate Jacoco coverage reports for the CoreRelease build
jacocoFdroidDebugCodeCoverage - Generate Jacoco coverage reports for the FdroidDebug build
jacocoFdroidReleaseCodeCoverage - Generate Jacoco coverage reports for the FdroidRelease build

Verified ./gradlew jacocoCoreDebugCodeCoverage generates files with expected content:

• build/reports/jacoco/jacocoCoreDebugCodeCoverage/jacocoCoreDebugCodeCoverage.xml
• build/reports/jacoco/jacocoCoreDebugCodeCoverage/html/index.html

The github action/workflow fails to post a comment to the PR when run. I'm not sure what's causing that. I've enabled debug logging on the action/workflow but someone with repo management permissions may need to help me understand what's going wrong with the token permissions.

Related issue

• Add code coverage for unit tests to Scribe Android #196

[github-actions]

Thank you for the pull request!

The Scribe team will do our best to address your contribution as soon as we can. The following is a checklist for maintainers to make sure this process goes as well as possible. Feel free to address the points below yourself in further commits if you realize that actions are needed :)

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Maintainer checklist

• The linting and formatting workflows within the PR checks do not indicate new errors in the files changed

• The CHANGELOG has been updated with a description of the changes for the upcoming release and the corresponding issue (if necessary)