Components: Extract Undo/Redo buttons as reusable components

[youknowriad]

Extract a reusable Undo/Redo components to the editor/components folder.
Needed to be able to separate the edit-post and editor module

Expect some similar PRs today, I'm going to merge them as soon as the tests pass, they consist of moving some files around.

Testing instructions

• Check that the undo/redo buttons work

[codecov]

Codecov Report

Merging #3640 into master will decrease coverage by 0.02%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #3640      +/-   ##
==========================================
- Coverage   36.85%   36.83%   -0.03%     
==========================================
  Files         268      270       +2     
  Lines        6640     6644       +4     
  Branches     1201     1201              
==========================================
  Hits         2447     2447              
- Misses       3541     3545       +4     
  Partials      652      652

Impacted Files	Coverage Δ
editor/components/editor-history/redo.js	0% <0%> (ø)
editor/components/editor-history/undo.js	0% <0%> (ø)
editor/edit-post/header/header-toolbar/index.js	0% <0%> (ø)	⬆️

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