Add docs/requirements.* to pin python versions for RTD build

docs/conf.py

@@ -94,7 +94,7 @@
 #
 # This is also used if you do content translation via gettext catalogs.
 # Usually you set "language" from the command line for these cases.
-language = None
+language = 'en'
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.

docs/requirements.in

@@ -0,0 +1,2 @@
+Sphinx>=5,<6
+sphinx_rtd_theme

docs/requirements.txt

@@ -0,0 +1,57 @@
+#
+# This file is autogenerated by pip-compile with Python 3.10
+# by the following command:
+#
+#    pip-compile docs/requirements.in
+#
+alabaster==0.7.16
+    # via sphinx
+babel==2.14.0
+    # via sphinx
+certifi==2024.2.2
+    # via requests
+charset-normalizer==3.3.2
+    # via requests
+docutils==0.19
+    # via
+    #   sphinx
+    #   sphinx-rtd-theme
+idna==3.6
+    # via requests
+imagesize==1.4.1
+    # via sphinx
+jinja2==3.1.3
+    # via sphinx
+markupsafe==2.1.5
+    # via jinja2
+packaging==23.2
+    # via sphinx
+pygments==2.17.2
+    # via sphinx
+requests==2.31.0
+    # via sphinx
+snowballstemmer==2.2.0
+    # via sphinx
+sphinx==5.3.0
+    # via
+    #   -r docs/requirements.in
+    #   sphinx-rtd-theme
+    #   sphinxcontrib-jquery
+sphinx-rtd-theme==2.0.0
+    # via -r docs/requirements.in
+sphinxcontrib-applehelp==1.0.8
+    # via sphinx
+sphinxcontrib-devhelp==1.0.6
+    # via sphinx
+sphinxcontrib-htmlhelp==2.0.5
+    # via sphinx
+sphinxcontrib-jquery==4.1
+    # via sphinx-rtd-theme
+sphinxcontrib-jsmath==1.0.1
+    # via sphinx
+sphinxcontrib-qthelp==1.0.7
+    # via sphinx
+sphinxcontrib-serializinghtml==1.1.10
+    # via sphinx
+urllib3==2.2.1
+    # via requests