Prune artifacts in playground once a week instead of every minute on sunday
Prune artifacts in playground once a week instead of every minute on sunday

Test: N/A (GH Actions)
Change-Id: I79f4ce8190d61a17d22010a8a349d5a2ef7f5cba

androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx