Making a variable optional in an `else` block doesn't work for `try`/`else`

Bug Report

#11002 allowed making a variable optional in an else block; this appears not to work in an else block from a try.

To Reproduce

# t.py
def __() -> None:
    try:
        ...
    except ValueError as exc:
        e = exc
    else:
        e = None

$ mypy t.py
t.py:7: error: Incompatible types in assignment (expression has type "None", variable has type "ValueError")
Found 1 error in 1 file (checked 1 source file)

Expected Behavior

I expect this to pass, as it would if it were an if/else

Actual Behavior

As above.

Your Environment

• Mypy version used: 0.950
• Mypy command-line flags: n/a
• Mypy configuration options from mypy.ini (and other config files): n/a
• Python version used: Python 3.10.4 (main, Apr 26 2022, 19:42:59) [Clang 13.1.6 (clang-1316.0.21.2)]
• Operating system and version: MacOS 12.3.1 (21E258)

I'm not sure if this is expected, and try/except was out of scope for the original feature, or whether this is a bug.

Inizia eseguendo l'esempio t.py segnalato con mypy 0.950 e confronta il suo comportamento try/except/else con il comportamento if/else descritto in issue #11002. Traccia il percorso del controllo dei tipi per le assegnazioni attraverso i blocchi try, quindi aggiungi un test di regressione per l'esempio e conferma che mypy accetta l'assegnazione di None senza introdurre errori.