build: debug apk come with application suffix

Instead of using the same one as Release, app.revanced.manager.flutter - We add .debug to it, yay, co-installation of two variants!

android/app/build.gradle

@@ -59,6 +59,15 @@ android {
                 abiFilters 'arm64-v8a', 'armeabi-v7a', 'x86_64'
             }
         }
+        debug {
+            shrinkResources false
+            minifyEnabled false
+            signingConfig signingConfigs.debug
+            applicationIdSuffix ".debug"
+            ndk {
+                abiFilters 'arm64-v8a', 'armeabi-v7a', 'x86_64'
+            }
+        }
     }
 
     packagingOptions {