fix: update config-file.md (#159)

just add a true to android.packageName because it is required option

Co-authored-by: Rob Walker <robert.walker@formidable.com>

Author: iPagar

docs/introduction/config-file.md

@@ -24,7 +24,7 @@ The config file - which unless specified in the cli should live in `./owl.config
 | `android.buildCommand` | false    |           | Overrides the `assembleDebug` gradle command. Should build the apk                           |
 | `android.buildType`    | false    | `Release` | Can be one of `debug` or `release`. Used to call either `assembleDebug` or `assembleRelease` |
 | `android.binaryPath`   | false    |           | The path to the binary, if you are using a custom build command                              |
-| `android.packageName`  |          |           | The package name/unique identifier of the app                                                |
+| `android.packageName`  | true     |           | The package name/unique identifier of the app                                                |
 | `android.quiet`        | false    |           | Passes the quiet flag to `gradlew`                                                           |
 
 ### Example