Add "Getting help" page

[etiennebacher]

Related to https://github.com/easystats/easystats/issues/265

[codecov[bot]]

Codecov Report

Merging #297 (975efd2) into main (3d5cd1e) will not change coverage. The diff coverage is n/a.

:exclamation: Current head 975efd2 differs from pull request most recent head 799b016. Consider uploading reports for the commit 799b016 to get more accurate results

@@           Coverage Diff           @@
##             main     #297   +/-   ##
=======================================
  Coverage   64.92%   64.92%           
=======================================
  Files          43       43           
  Lines        1759     1759           
=======================================
  Hits         1142     1142           
  Misses        617      617