obshistory: omit duplicate notes of obsolescence operations
When folding changesets, it's possible to provide a --note flag to e.g. fold or
prune, which will store a note for that operation. But since there would be
more than one marker for the fold operation and the provided note would be
stored in all of them, _markersnotes() previously would return the same text
message many times. We don't really want to see the same thing over and over,
so let's make notes a set().
This will also make unrelated operations with the same note show the message
only once, which is probably an improvement too.
include CHANGELOG
include COPYING
include hgext3rd/topic/README
include MANIFEST.in
include README
include setup.py
recursive-include tests *.py *.sh *.t
include docs/makefile
include docs/*.py
include docs/README
include docs/*.rst
include docs/static/*.svg
include docs/tutorials/*.t
include docs/tutorial/standalone.html
recursive-include docs/figures *.svg *.png
recursive-include docs/tutorial *.css *.js *.md *.py *.rst *.sh *.t
exclude docs/tutorial/.netlify
exclude .gitlab-ci.yml
exclude ./hgext3rd/evolve/legacy.py
exclude .hg-format-source
exclude Makefile
exclude tests/test-drop.t
exclude tests/test-inhibit.t
exclude tests/test-oldconvert.t
prune contrib
prune debian
prune .gitlab
prune hgext3rd/evolve/hack