Convert parallel setting to int

[radarhere]

LInt has started failing - https://github.com/python-pillow/Pillow/actions/runs/31563474566/job/94010414409#step:6:22

setup.py:383: error: Incompatible types in assignment (expression has type
"str | None", variable has type "int | None")  [assignment]
            self.parallel = configuration.get("parallel", [None])[-1]
                            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Found 1 error in 1 file (checked 303 source files)

[hugovk]

Likely caused by today's https://pypi.org/project/types-setuptools/84.0.0.20260812/

---

We already have this value at:

Pillow/setup.py

Line 35 in a9fd14b

default = int(configuration.get("parallel", ["0"])[-1])

Shall we rename that to something like parallel_default and:

Suggested change

	if "parallel" in configuration:
	self.parallel = int(configuration["parallel"][-1])
	self.parallel = parallel_default

Or use the same pattern as there:

Suggested change

	if "parallel" in configuration:
	self.parallel = int(configuration["parallel"][-1])
	self.parallel = int(configuration.get("parallel", ["0"])[-1])