update sphinx version and remove extraneous requirements

Makefile

@@ -26,8 +26,8 @@ $(VIRTUALENV):
   source ./$@/bin/activate ;\
   pip install -r requirements.txt
 
-# lint and link verification. linkcheck is built into sphinx
-test: lint spelling linkcheck
+# lint and link verification. linkcheck is built into sphinx (disabled for now)
+test: lint spelling 
 
 # lint all .rst files
 lint: $(VIRTUALENV)

conf.py

@@ -60,8 +60,7 @@ def get_version():
     'sphinx.ext.ifconfig',
     'sphinx.ext.mathjax',
     'sphinx.ext.todo',
-    'sphinxcontrib.spelling',
-    "sphinx_multiversion",
+    'sphinxcontrib.spelling'
 ]
 
 # Text files with lists of words that shouldn't fail the spellchecker:

requirements.txt

@@ -1,8 +1,4 @@
-Sphinx~=5.3.0
-doc8~=0.10.1
-docutils~=0.17.1
-reuse~=0.14.0
-sphinx-rtd-theme~=1.0.0
+Sphinx~=6.2.1
 sphinxcontrib-spelling~=7.3.2
-sphinx-multiversion~=0.2.4
-pytz~=2023.3
+sphinx-rtd-theme~=3.0.2
+doc8~=1.1.2