[firebase_ml_vision] Add rawBytes to the Barcode class (#1816)

[the-mars-rover]

Description

• Upgrade of the firebase-ml-vision android dependancy to 24.0.1 to allow access to getRawBytes.
• In the example, upgraded the firebase-ml-vision-image-label-model and firebase-ml-vision-face-model android dependencies to 19.0.0 to accommodate the aforementioned upgrade of firebase-ml-vision (Without these upgrades version solving will fail).
• Added rawBytes to the Barcode class. Populated this with getRawBytes for android and with rawData for iOS

Related Issues

• [firebase_ml_vision] Add rawBytes to the Barcode class #1816

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[the-mars-rover]

@googlebot I fixed it.

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[collinjackson]

Thanks for the PR! Can we get a unit test for this? See https://github.com/FirebaseExtended/flutterfire/blob/master/packages/firebase_ml_vision/test/firebase_ml_vision_test.dart

[collinjackson]

It's a bit unfortunate that we have to release this as a breaking change. If we landed #39 then we wouldn't have to make this a breaking change.

[the-mars-rover]

Thanks for the PR! Can we get a unit test for this? See https://github.com/FirebaseExtended/flutterfire/blob/master/packages/firebase_ml_vision/test/firebase_ml_vision_test.dart

Updated the PR by adding rawBytes to some existing unit tests - I believe this will suffice?:)

[the-mars-rover]

It's a bit unfortunate that we have to release this as a breaking change. If we landed #39 then we wouldn't have to make this a breaking change.

Definitely unfortunate. Will keep an eye on #39 and update this PR accordingly if it lands 💯

[the-mars-rover]

Solved the merge conflicts