[C++][CI] Python grpcio built from source on ARM64 Ubuntu 20.04 build

[pitrou]

Describe the bug, including details regarding any error messages, version, and platform.

See here:
https://github.com/apache/arrow/actions/runs/10556611086/job/29270139087#step:7:3659

#13 19.15   Building wheel for grpcio (setup.py): started
[...]
#13 878.9   Building wheel for grpcio (setup.py): finished with status 'done'
#13 879.0   Created wheel for grpcio: filename=grpcio-1.59.0-cp38-cp38-linux_aarch64.whl size=99147440 sha256=3721904a25fa0614a1deb51ba97420c92b740ba436c2c5404905c067c717b26a

As we can, this step alone takes around 14 minutes.

Yet there is a binary package available for the given version and architecture ( grpcio-1.59.0-cp38-cp38-manylinux_2_17_aarch64.whl):
https://pypi.org/project/grpcio/1.59.0/#files

My guess is that the pip version is too old to support it. We should therefore upgrade pip.

Component(s)

C++, Continuous Integration

[pitrou]

cc @raulcd @jorisvandenbossche

[pitrou]

This was fixed by #43852