Improve build process, according to "Build multiple APKs"...

.gitlab-ci.yml

android/.gitignore

android/app/build.gradle

android/app/src/debug/AndroidManifest.xml

android/app/src/main/AndroidManifest.xml

...src/main/java/org/benoitharrault/random/MainActivity.java

...src/main/kotlin/org/benoitharrault/random/MainActivity.kt

android/app/src/profile/AndroidManifest.xml

android/build.gradle

android/gradle.properties

android/gradle/wrapper/gradle-wrapper.properties

android/settings.gradle

pubspec.yaml