Change sphinx-tabs repo (ros2#813)

* Change sphinx-tabs repo

Signed-off-by: maryaB-osr <[email protected]>

* linter

Signed-off-by: maryaB-osr <[email protected]>

* change to osrf fork

Signed-off-by: maryaB-osr <[email protected]>

Author: maryaB-osr

.travis.yml

@@ -3,7 +3,8 @@ python: 3.6
 sudo: false
 install:
   - pip3 install doc8 sphinx
-  - pip3 install git+https://github.com/Daltz333/sphinx-tabs@sphinx3
+  - pip3 install git+https://github.com/osrf/sphinx-tabs
+
 script:
   - make html 2> stderr.log
   - cat stderr.log