Override upper constraints (r8, r7, r6, r5)

Several inherited changes to upper constraints are
incompatible with the version of Sphinx used in
StarlingX. This change bumps sphinx to 5.0 to
satisfy new requirements.
Specify lang value for sphinx 5

Change-Id: If5d9680da60e9fc29b671755b246398f20fe76e1
Signed-off-by: Ron Stone <ronald.stone@windriver.com>

doc/requirements.txt

@@ -1,4 +1,5 @@
-sphinx==4.2.0
+#sphinx==4.2.0
+sphinx==5.0
 openstackdocstheme>=2.2.1,<=2.3.1 # Apache-2.0
 docutils==0.17.1
 PyYAML==6.0

doc/source/conf.py

@@ -62,7 +62,7 @@ master_doc = 'index'
 #
 # 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.