Media view includes media_bulk_form but no implementation

Problem/Motivation

Found while reviewing #2831937: Add "Image" MediaSource plugin that the media view includes the bulk form actions column, which does not work. That is because the actions were removed from the initial media entity patch but not from the view. So now the view and the media views config schema has the media_bulk_form plugin but no implementation exists. That was postponed until #2877383: Add action support to Media module.

Proposed resolution

Remove this until #2877383: Add action support to Media module is resolved or postpone removing it if #2877383: Add action support to Media module can be resolved *soon*.

Remaining tasks

User interface changes

None.

API changes

Media views config schema for non-existent plugin is removed. The plugin does not work anyway as the code is not there yet.

Data model changes

None.