display beta and rc versions in docs instead of 'develop' which is sh…

…own for -dev (non-release) versions

docs/conf.py

@@ -33,9 +33,9 @@
 # the stable version, displayed on front page of PDF extract X.Y version
 # from release by splitting the string into a list
 # using - as the delimeter, then getting the 1st item of the list
-# if version is beta, rc, and/or dev then set version to develop for
+# if version ends with -dev then set version to develop for
 # the documentation built for develop (not release)
-if len(release.split('-')) > 1:
+if len(release.split('-')) > 2:
     version = 'develop'
 else:
     version = f"{release.split('-')[0]}"