CompatHelper: add new compat entry for Documenter at version 1 for package docs, (keep existing compat)

[github-actions]

This pull request sets the compat entry for the Documenter package to 1 for package docs.
This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry.
It is your responsibility to make sure that your package tests pass before you merge this pull request.
Note: Consider registering a new release of your package immediately after merging this PR, as downstream packages may depend on this for tests to pass.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 51.94%. Comparing base (6e449ae) to head (60cb105).

❗ There is a different number of reports uploaded between BASE (6e449ae) and HEAD (60cb105). Click for more details.

HEAD has 4 uploads less than BASE

Flag	BASE (6e449ae)	HEAD (60cb105)
	5	1

Additional details and impacted files

@@             Coverage Diff             @@
##             main      #91       +/-   ##
===========================================
- Coverage   90.76%   51.94%   -38.82%     
===========================================
  Files          20       20               
  Lines        1472     1442       -30     
===========================================
- Hits         1336      749      -587     
- Misses        136      693      +557     

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