Build/Test Tools: update PHPUnit tests after [48323]. Disable and keep the...

Build/Test Tools: update PHPUnit tests after [48323]. Disable and keep the specific jQuery Migrate dependency tests for use in WP 5.6.

See #37110.
Built from https://develop.svn.wordpress.org/trunk@48324


git-svn-id: https://core.svn.wordpress.org/trunk@48093 1a063a9b-81f0-0310-95a4-ce76da25c4cd