Resolved GitHub actions bug due to new GitHub changes on 1 March 2021

[JonathanLeeWH]

• Amended app-test-container-no-docker-cache.yml and app-test-container.yml in response to recent changes by GitHub on 1 March 2021 involving dependabot pull requests running with read only permissions which resulted in GitHub Actions triggered by dependabot pull requests inability to read GitHub Secrets. The changes by GitHub resulted in GitHub Actions continuous integration not working for dependabot pull requests due to inability to read GitHub Secrets.

• Resolved bug Issues with GitHub Actions continuous integration for dependabot pull requests #172

Note: As app-test-container.yml is currently disabled it is not amended with the bug fixes but references are added for future references if the workflow is to be used in the future.

References:

• https://docs.github.com/en/actions/reference/events-that-trigger-workflows#pull_request_target (Announcement of changes to be made to dependabot pull requests)
• https://securitylab.github.com/research/github-actions-preventing-pwn-requests/ (Recommended security mitigations by GitHub)
• Dependabot triggered Actions cant access secrets or use a writable token dependabot/dependabot-core#3253 (comment) (Ongoing GitHub issues by users in response to the changes)
• https://github.saobby.my.eu.orgmunity/t/dependabot-doesnt-see-github-actions-secrets/167104/31 (GitHub community discussion on the issue)
• https://docs.github.com/en/actions/reference/events-that-trigger-workflows#pull_request_target
• https://hugo.alliau.me/2021/05/04/migration-to-github-native-dependabot-solutions-for-auto-merge-and-action-secrets/#share-your-secrets-with-dependabot (Potential Auto merge dependencies solution in the future)