Merge branch 'release/1.7.x' into fix/merge-kerfuffle

# Conflicts:
#	Corona-Warn-App/src/main/java/de/rki/coronawarnapp/notification/NotificationHelper.kt
#	Corona-Warn-App/src/main/java/de/rki/coronawarnapp/risk/DefaultRiskLevels.kt
#	Corona-Warn-App/src/main/java/de/rki/coronawarnapp/worker/BackgroundWorkHelper.kt
#	Corona-Warn-App/src/main/java/de/rki/coronawarnapp/worker/DiagnosisTestResultRetrievalPeriodicWorker.kt
#	gradle.properties