Revert the mandatory backups feature.

Bug: 79736299
Test: make RunSettingsGoogleRoboTests
Test: make RunSettingsRoboTests

Change-Id: Ie9702664c0fb4daccdee74eac6080c959fe1b608

src/com/android/settings/enterprise/EnterprisePrivacyFeatureProvider.java

@@ -124,9 +124,4 @@ public interface EnterprisePrivacyFeatureProvider {
      * profile (if any).
      */
     int getNumberOfActiveDeviceAdminsForCurrentUserAndManagedProfile();
-
-    /*
-     * Returns whether backups are mandatory.
-     */
-    boolean areBackupsMandatory();
 }