Proposal: remove `gr.make_waveform` and remove `matplotlib` as a dependency (#9312)
* remove matplotlib
* add changeset
* remove tests, demo
* Fix the Lite worker to set the matplotlib backend engine only when the matplotlib package is installed
* add changeset
* Fix comment
---------
Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>
Co-authored-by: Yuichiro Tachibana (Tsuchiya) <t.yic.yt@gmail.com>