Fixes: #2453

Related PRs:
gutenberg WordPress/gutenberg#25951
WordPress-Android wordpress-mobile/WordPress-Android#13085

To test:

Layout Picker should show when creating a new page from My Site or Site Pages the Modal Layout Picker appears.

• Start by navigating to the Modal Layout Picker

Page Created (with content)

1. Select a Layout from the options in Modal Layout Picker
2. Select "Create Page"
   Expect to see the info notice banner appear under the navigation bar with the text "Page created"

• 🗒️ This is different than the mocks in the linked issue but aligns with the direction that was determined.

Blank Page Created

1. Select "Create Blank Page"
   Expect to see the info notice banner appear under the navigation bar with the text "Blank page created"

• 🗒️ This is different than the mocks in the linked issue but aligns with the direction that was determined.

Blog Post Created

1. Create a new blog post

• This should not display the notice bar

Open existing Page Created

1. Open an existing page (either published or draft)

• This should not display the notice bar

PR submission checklist:

• I have considered adding unit tests where possible.
• I have considered if this change warrants user-facing release notes more info and have added them to RELEASE-NOTES.txt if necessary.