Docs: pin sphinx-lint (GH-97992)

Doc/requirements.txt

@@ -10,7 +10,7 @@ blurb
 # sphinx-lint 0.6.2 yields many default role errors due to the new regular
 # expression used for default role detection, so we don't use the version
 # until the errors are fixed.
-sphinx-lint<1,!=0.6.2
+sphinx-lint==0.6.1
 
 # The theme used by the documentation is stored separately, so we need
 # to install that as well.