chore: update version name and version code in build gradle

Author: Fandroid745

.idea/workspace.xml

@@ -14,8 +14,8 @@ android {
         applicationId "com.opennotes"
         minSdk 24
         targetSdk 35
-        versionCode 3  // Updated for v1.2 release
-        versionName "1.2"  // Updated for v1.2 release
+        versionCode 4
+        versionName "1.3"
 
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         vectorDrawables.useSupportLibrary = true