build: tweak the docs build step

Author: nedbat

Diff for: ci/update_rtfd.py

@@ -9,7 +9,7 @@
 
 # How many from each level to show.
 NUM_MAJORS = 3
-NUM_MINORS = 4
+NUM_MINORS = 3
 OLD_MINORS = 1
 NUM_MICROS = 1
 OLD_MICROS = 1

Diff for: howto.txt

@@ -65,7 +65,6 @@
             - https://github.com/nedbat/coveragepy/actions/workflows/publish.yml
 - Tag the tree, update GitHub releases and comment on issues:
     $ make clean tag github_releases comment_on_fixes
-$ deopvars
 - Bump version:
     $ make bump_version
 - Update readthedocs
@@ -74,7 +73,9 @@ $ deopvars
         - keep just the latest version of each x.y release, make the rest active but hidden.
             - pre-releases should be hidden
     - IF NOT PRE-RELEASE:
+        $ opvars
         $ make update_rtd
+$ deopvars
 - Once CI passes, merge the bump-version branch to master and push it
     $ gshipit