Update flag for PendingIntent

Targeting S+ (version 31 and above) requires that one of FLAG_IMMUTABLE or FLAG_MUTABLE be specified when creating a PendingIntent. https://android-build.googleplex.com/builds/tests/view?invocationId=I61100009516081227&testResultId=TR63625744243240459

Bug: 190354625
Test: Manually
Change-Id: Ia023b54fac18436caf35c36426c7044d8289ae58
1 file changed