Merge branch 'bugfix/py3_link_roles' into 'release/v3.0'

docs: Add build support for python3 (backport v3.0)

See merge request idf/esp-idf!2919

docs/link-roles.py

@@ -6,9 +6,9 @@ from repo_util import run_cmd_get_output
 def get_github_rev():
     path = run_cmd_get_output('git rev-parse --short HEAD')
     tag = run_cmd_get_output('git describe --exact-match')
-    print 'Git commit ID: ', path
+    print ('Git commit ID: ', path)
     if len(tag):
-        print 'Git tag: ', tag
+        print ('Git tag: ', tag)
         path = tag
     return path