possibly-undefined not catching unbound variable in try/finally block

Bug Report

The possibly-undefined check is not catching a possibly unbound variable when it's used within a finally block

To Reproduce

The following code raises NameError: name 'val' is not defined at runtime but passes he possibly-undefined check:

def foo() -> int:
    raise Exception()

try:
    val = foo()
except ValueError:
    val = 1
finally:
    print(val)

Your Environment

• Mypy version used: 1.10.0
• Mypy command-line flags: None
• Mypy configuration options from mypy.ini (and other config files):

[tool.mypy]
enable_error_code = ["possibly-undefined", "redundant-expr", "truthy-bool"]
incremental = false
strict = true
warn_unreachable = true

• Python version used: 3.9.17

No repository files or tests are named. Start by running the provided Python snippet with mypy 1.10.0 and the shown configuration, then trace the possibly-undefined analysis for try/finally; done means the unbound val use is reported and a regression test covers the case.