DOC: [MAINTENANCE] Disable Sphinx version limit in GitHub CI due to n…

…ew sphinx-vhdl version

.github/workflows/doc.yml

@@ -21,7 +21,7 @@ jobs:
       - name: Setup and build
         run: |
           sudo apt-get install python3-pip
-          pip3 install sphinx==5.3.0 sphinx-vhdl sphinx_rtd_theme GitPython
+          pip3 install sphinx sphinx-vhdl sphinx_rtd_theme GitPython
           mkdir public
           mkdir public/html
           cp doc/source/index.html public/html/