fixed failing CI, missing requirement

.gitlab-ci.yml

@@ -49,8 +49,9 @@ pages:
   script:
     - pyenv install 3.6.9
     - pyenv shell 3.6.9
-    - cd sphinx-doc/
     - pip install --upgrade pip
+    - pip install -r requirements.txt
+    - cd sphinx-doc/
     - pip install -r requirements_sphinx.txt
     - make html
     - cp -r _build/html ../public

sphinx-doc/requirements_sphinx.txt

@@ -10,6 +10,7 @@ Click==7.0
 commonmark==0.9.1
 cycler==0.10.0
 decorator==4.4.2
+dios==0.6.0
 docutils==0.16
 dtw==1.4.0
 idna==2.10