PEP 604: Fix markup (#1539)

"Change only PEP 484" is not sub idea of "Add a new operator ".

Author: methane

pep-0604.rst

@@ -136,8 +136,8 @@ CONS:
   Pytype, and who knows what else (it's a minor change see "Reference Implementation"
 
 
-Change only PEP 484 (Type hints) to accept the syntax ``type1 | type2`` ?
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+2. Change only PEP 484 (Type hints) to accept the syntax ``type1 | type2`` ?
+----------------------------------------------------------------------------
 
 PEP 563 (Postponed Evaluation of Annotations) is enough to accept this proposition,
 if we accept to not be compatible with the dynamic evaluation of annotations (``eval()``).
@@ -153,7 +153,7 @@ if we accept to not be compatible with the dynamic evaluation of annotations (``
       File "<string>", line 1, in <module>
     TypeError: unsupported operand type(s) for |: 'type' and 'type'
 
-2. Extend ``isinstance()`` and ``issubclass()`` to accept ``Union`` ?
+3. Extend ``isinstance()`` and ``issubclass()`` to accept ``Union`` ?
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