Using internal cropper as default

[etoledom]

Part of #381

Description

This PR uses the image cropper from https://github.com/Automattic/Gravatar-SDK-iOS/pull/407 as the default image cropper on the avatar picker.

After this, we are free to use PHPickerViewController.

Testing Steps

• Run the SwiftUI demo app.
• Open the Avatar picker view demo screen.
• Open the avatar picker.
• Upload a new image by Chose a photo.
• Select an image
  • Check that the picker is presented with title Resize & Crop.
  • Check that the image is cropped as expected.
• Go back to the Avatar picker view demo screen (closing the avatar picker).
• Switch ON Custom image cropper.
• Repeat the previous step to chose an image.
  • Check that the dummy image cropper is shown.

[wpmobilebot]

📲 You can test the changes from this Pull Request in Gravatar SwiftUI Prototype Build by scanning the QR code below to install the corresponding build.

	App Name	Gravatar SwiftUI Prototype Build
	Build Number	1273
	Version	1.0
	Bundle ID	com.automattic.gravatar-sdk-demo-swiftui.prototype-build
	Commit	890afcd824e2107bf0d98a7d8641e0f11a4e0770
	App Center Build	Gravatar SDK Demo - SwiftUI #140

Automatticians: You can use our internal self-serve MC tool to give yourself access to App Center if needed.

[wpmobilebot]

📲 You can test the changes from this Pull Request in Gravatar UIKit Prototype Build by scanning the QR code below to install the corresponding build.

	App Name	Gravatar UIKit Prototype Build
	Build Number	1273
	Version	1.0
	Bundle ID	com.automattic.gravatar-sdk-demo-uikit.prototype-build
	Commit	890afcd824e2107bf0d98a7d8641e0f11a4e0770
	App Center Build	Gravatar SDK Demo - UIKit #141

Automatticians: You can use our internal self-serve MC tool to give yourself access to App Center if needed.