Avoid using Sphinx 9 for mis-parsed annotations

sphinx-doc/sphinx#14159

Author: inducer

ci-support.sh

@@ -687,9 +687,8 @@ run_examples()
 build_docs()
 {
   if test "$CI_SUPPORT_SPHINX_VERSION_SPECIFIER" = ""; then
-    # >=3.2.1 for https://github.com/sphinx-doc/sphinx/issues/8084
-    # >=4.0.2 because sphinx 4 is nice :D
-    CI_SUPPORT_SPHINX_VERSION_SPECIFIER=">=4.0.2"
+    # <9 for https://github.com/sphinx-doc/sphinx/issues/14159
+    CI_SUPPORT_SPHINX_VERSION_SPECIFIER="<9"
   fi
 
   # Two separate installs to trick sphinx into not precisely enforcing dependencies.