Standardize Distributed Alert Copy

[cdwieber]

Partially addresses #611

Description of the Change

Per #611, the notification copy between the classic and Gutenberg editors was inconsistent. This PR simply updates said verbiage for consistency between Gutenberg and Classic.

Alternate Designs

The original spec called for an inline link to the original post as opposed to the "View Original" action in the Gutenberg notification. As outlined in a comment in #611, the notification architecture might have to be altered to account for this, so this PR will only address the verbiage.

Benefits

Verbiage for the notifications will be more consistent across editors.

Possible Drawbacks

None.

Verification Process

1. Visit a distributed post in the Gutenberg editor, and ensure that the verbiage matches that of the Classic editor.

Checklist:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my change. | WPAcceptance test changed accordingly.
• All new and existing tests passed.

Applicable Issues

The inline link still needs to be added to the Gutenberg notification so as to match the Classic

Changelog Entry

Changed some notification text for added consistency.