Update release guide

Add note about closing old milestones

Separate push steps for branch and tag

Author: ksunden

doc/devel/release_guide.rst

@@ -83,7 +83,8 @@ Micro versions should instead read::
 Check all active milestones for consistency. Older milestones should also backport
 to higher meso versions (e.g. ``v3.6.3`` and ``v3.6-doc`` should backport to both
 ``v3.6.x`` and ``v3.7.x`` once the ``v3.7.x`` branch exists and while PR backports are
-still targeting ``v3.6.x``)
+still targeting ``v3.6.x``). Close milestones (and remilestone any issues/PRs) for versions
+which are unlikely to be produced.
 
 Create the milestone for the next-next meso release (i.e. ``v3.9.0``, as ``v3.8.0``
 should already exist). While most active items should go in the next meso release,
@@ -294,9 +295,14 @@ it is important to move all branches away from the commit with the tag [#]_::
 
   git commit --allow-empty
 
+Push the branch to GitHub. This is done prior to pushing the tag as a last step in ensuring
+that the branch was fully up to date::
+
+  git push DANGER v3.7.x
+
 Finally, push the tag to GitHub::
 
-  git push DANGER v3.7.x v3.7.0
+  git push DANGER v3.7.0
 
 Congratulations, the scariest part is done!
 This assumes the release branch has already been made.