TinyMCE: Run the filters for the Classic block.

The `wp_editor_settings` and `disable_captions` filters need to be run for the Classic Block.

This fixes possible regressions in plugins that use these filters, and plugins that use them to add filters for the buttons, external plugins, etc.

Props azaozz.

Merges [43914] into trunk.

Fixes #45348.
Built from https://develop.svn.wordpress.org/trunk@44265


git-svn-id: https://core.svn.wordpress.org/trunk@44095 1a063a9b-81f0-0310-95a4-ce76da25c4cd