Fix help message url for "None and Optional handling" section (#19252)

Fixes #19251

Author: guywilsonjr

mypy/main.py

@@ -785,7 +785,7 @@ def add_invertible_flag(
         title="None and Optional handling",
         description="Adjust how values of type 'None' are handled. For more context on "
         "how mypy handles values of type 'None', see: "
-        "https://mypy.readthedocs.io/en/stable/kinds_of_types.html#%3Cspan%20class="x x-first x-last">no-strict-optional",
+        "https://mypy.readthedocs.io/en/stable/kinds_of_types.html#%3Cspan%20class="x x-first x-last">optional-types-and-the-none-type",
     )
     add_invertible_flag(
         "--implicit-optional",