This brings some consistency to how the introduction is displayed for the Beta Testing, Featured, and Recommended tabs of the Add Plugins screen.
This commit also reorders the `switch` cases for the text in the same order as they are displayed.
Follow-up to [9141], [30889], [36297].
Props sabbir1991, kapilpaul.
Fixes#55389.
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git-svn-id: http://core.svn.wordpress.org/trunk@52525 1a063a9b-81f0-0310-95a4-ce76da25c4cd