v21.0.1

• [Improvement] ANDROID_APP_VERSION and ANDROID_APP_REPOSITORY values now set correctly in Dockerfile (by @CodeWithEmad)

• [Feature] ANDROID_APP_ID introduced to set the APPLICATION_ID inside tutor.yaml (by @CodeWithEmad)

• [Chore] Remove unnecessary hatch definition for version. (by @Abdul-Muqadim-Arbisoft)

• [Feature] Make the Android app's tutor.yaml fully customisable from Tutor config (#48). All commonly tweaked fields (Firebase, Segment, Braze, Google, Microsoft, Facebook, Branch, agreement URLs, discovery/program settings, feature flags, etc.) are now exposed as ANDROID_* settings, and a new android-tutor-yaml patch lets plugins append or override any value in the rendered file. (by @Abdul-Muqadim-Arbisoft)