Merge branch 'doc/view_github_link' into 'master'

docs: add 'edit-on-github' link to html theme

Closes IDF-1504

See merge request espressif/esp-idf!8629

docs/idf_extensions/link_roles.py

@@ -8,19 +8,7 @@ import subprocess
 from docutils import nodes
 from collections import namedtuple
 from sphinx.transforms.post_transforms import SphinxPostTransform
-
-
-def get_github_rev():
-    path = subprocess.check_output(['git', 'rev-parse', '--short', 'HEAD']).strip().decode('utf-8')
-    try:
-        tag = subprocess.check_output(['git', 'describe', '--exact-match']).strip().decode('utf-8')
-    except subprocess.CalledProcessError:
-        tag = None
-    print('Git commit ID: ', path)
-    if tag:
-        print('Git tag: ', tag)
-        return tag
-    return path
+from get_github_rev import get_github_rev
 
 
 # Creates a dict of all submodules with the format {submodule_path : (url relative to git root), commit)}