Update kinds_of_types.rst: keep old anchor for #no-strict-optional

Not sure if this will work, since something else has the same anchor on a different page... See python#19252, though.

Author: wyattscarpenter

docs/source/kinds_of_types.rst

@@ -294,6 +294,7 @@ isn't supported by the runtime with some limitations, if you use
    def f(x: int | str) -> None:   # OK on Python 3.7 and later
        ...
 
+.. _no-strict-optional:
 .. _strict_optional:
 
 Optional types and the None type