Fix NPE at AppDb#findUsage

This should never have happened since the non-null checks have passed. But in
reality, it still happens on ZTE Blade A75 5G.

Signed-off-by: Muntashir Al-Islam <muntashirakon@riseup.net>

Author: MuntashirAkon

app/src/main/java/io/github/muntashirakon/AppManager/db/utils/AppDb.java

@@ -27,6 +27,7 @@
 import java.util.List;
 import java.util.ListIterator;
 import java.util.Map;
+import java.util.Objects;
 import java.util.Set;
 
 import io.github.muntashirakon.AppManager.backup.BackupUtils;
@@ -436,7 +437,7 @@ private static int findIndexOfApp(@NonNull List<App> appList, @NonNull String pa
     @Nullable
     private static PackageUsageInfo findUsage(@NonNull List<PackageUsageInfo> usageInfoList, @NonNull String packageName, @UserIdInt int userId) {
         for (PackageUsageInfo usageInfo : usageInfoList) {
-            if (usageInfo.userId == userId && usageInfo.packageName.equals(packageName)) {
+            if (usageInfo.userId == userId && Objects.equals(usageInfo.packageName, packageName)) {
                 return usageInfo;
             }
         }