[RN] Increment short app version from 1.2 to 1.3

Now that Apple have approved build 1.2.199 for release in the App Store,
the short app version needs to be incremented; otherwise, no new builds
can be uploaded to TestFlight and, respectively, for release in the App
Store.

android/app/build.gradle

@@ -91,7 +91,7 @@ android {
         minSdkVersion 16
         targetSdkVersion 22
         versionCode Integer.parseInt("${version}")
-        versionName "1.2.${version}"
+        versionName "1.3.${version}"
         ndk {
             abiFilters 'armeabi-v7a', 'x86'
         }

ios/app/Info.plist

@@ -17,7 +17,7 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>1.2</string>
+	<string>1.3</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleURLTypes</key>