Remove fixed screen orientation

[nbradbury]

Fixes #21084

Previously we had several screens fixed into either portrait or landscape. This PR addresses this by removing all fixed orientation. The following screens are affected:

• ReaderVideoViewerActivity - I could never get this activity to appear. I created a blog post with a video but when I viewed that post in the reader and tapped a video to make it full-screen that activity didn't appear. Likewise, videos in other reader posts didn't result in this activity appearing. So I opted to force it to appear by adding ReaderActivityLauncher.showReaderVideoViewer(requireActivity(), "https://youtu.be/eWRn80UOsqw?si=78nqh1LqykHXqHtV") to the end of MySite.onViewCreated - and it crashed with an NPE! I fixed that and it worked just fine in both portrait and landscape.
• Blaze screens - these had issues with being rotated due to state not being saved & restored, but this has been addressed
• SupportWebViewActivity - I was unable to test this (in my case, "Contact support" doesn't work in debug builds), so I'd appreciate the reviewer testing this one
• JetpackMigrationActivity - this is a hard one to test, so I recommend adding showJetpackMigrationDeleteWP() at the end of MySite.onViewCreated to force it to appear

[dangermattic]

	1 Warning
:warning:	PR is not assigned to a milestone.

Generated by :no_entry_sign: Danger

[wpmobilebot]

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

	App Name	WordPress
	Flavor	Jalapeno
	Build Type	Debug
	Version	pr21481-212f32b
	Commit	212f32b52d44ee3489638742b057df346588a10c
	Direct Download	wordpress-prototype-build-pr21481-212f32b.apk

Note: Google Login is not supported on these builds.

[wpmobilebot]

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

	App Name	Jetpack
	Flavor	Jalapeno
	Build Type	Debug
	Version	pr21481-212f32b
	Commit	212f32b52d44ee3489638742b057df346588a10c
	Direct Download	jetpack-prototype-build-pr21481-212f32b.apk

Note: Google Login is not supported on these builds.

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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