refactor: Change context field to volatile

Field is set from main thread, but can be immediately accessed by non main threads.

extensions/shared/library/src/main/java/app/revanced/extension/shared/Utils.java

@@ -46,7 +46,7 @@ import app.revanced.extension.shared.settings.preference.ReVancedAboutPreference
 public class Utils {
 
     @SuppressLint("StaticFieldLeak")
-    private static Context context;
+    private static volatile Context context;
 
     private static String versionName;
     private static String applicationLabel;