Fix: remove parallel build bc it conflicts with usec theme

Author: clemens-fricke

.github/workflows/docs.yml

@@ -28,7 +28,7 @@ jobs:
 
       - name: Sphinx build
         run: |
-          sphinx-build -W -b html docs/source docs/build -j auto
+          sphinx-build -W -b html docs/source docs/build
 
       - name: Deploy
         uses: peaceiris/actions-gh-pages@v3

docs/Makefile

@@ -3,7 +3,7 @@
 
 # You can set these variables from the command line, and also
 # from the environment for the first two.
-SPHINXOPTS    ?= -j auto
+SPHINXOPTS    ?=
 SPHINXBUILD   ?= sphinx-build
 SPHINXAPIDOC  ?= sphinx-apidoc
 MODULEDIR     ?= ../gustaf