Add option to pick image by using the camera

[etoledom]

Description

Adding the option to upload a new Avatar image by taking a photo using the camera.

Note: We are forcing the sources to be used by the Avatar Picker. I'm not sure if we should make it an option to the 3rd party dev, since this is Gravatar domain.

In case we want to give this option, we can do it in a next PR.

Testing Steps

• Build the SwiftUI demo app on device (or use the App Center build).
• Add a new avatar using the device's camera.
• Check that the new image can be selected as the avatar.

[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	1123
	Version	1.0
	Bundle ID	com.automattic.gravatar-sdk-demo-swiftui.prototype-build
	Commit	73289cfb8121b390c3eec57d977d08675ae1850f
	App Center Build	Gravatar SDK Demo - SwiftUI #55

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	1123
	Version	1.0
	Bundle ID	com.automattic.gravatar-sdk-demo-uikit.prototype-build
	Commit	73289cfb8121b390c3eec57d977d08675ae1850f
	App Center Build	Gravatar SDK Demo - UIKit #56

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

[etoledom]

2. We do the trick here mentioned here. Which would look sth like this:

I implemented this and seems to work good, for as long as Apple don't change the camera background color 🙈

1. Add bottom padding with the amount of safe area bottom inset. In this case we need to use GeometryReader to get the safe area bottom inset i think 🤔

This seems to give a similar result to not call .ignoresSafeArea(), right? And it leaves an empty space at the bottom.

I'd go with the color fill for now.

[etoledom]

@pinarol - Ready for another look 👀