Pin setuptools-scm dependency version

[FabianNiehaus]

Description

The setuptools-scm dependency in setup.cfg did not have a version specified, leading to the issues described in #2449 after a faulty release of setuptools-scm was published.
To avoid this issue in the future, the last version before that faulty update is now pinned.

Checklist - did you ...

• Add a CHANGELOG entry if necessary?
• Add / update tests if necessary? -> Not needed
• Add new / update outdated documentation? -> Not needed

[ichard26]

I'm not a big fan of pinning setuptools-scm but if we are going to go down this route, I'd ask that we move the setuptools-scm requirement definition to the build-system.requires field in pyproject.toml.

[ichard26]

Suggested change

	- Pin `setuptools-scm` dependency version (#2449)
	- Pin `setuptools-scm` dependency version (#2450)

We do it by PR number not issue number ^^

[FabianNiehaus]

I'm not a big fan of pinning setuptools-scm but if we are going to go down this route, I'd ask that we move the setuptools-scm requirement definition to the build-system.requires field in pyproject.toml.

I am not too familiar with this, but setuptools-scm is already present in pyproject.toml (without version pinning). What is the purpose of setup.cfg in this case? Can we pin the version in pyproject.toml and remove setup.cfg?

[ichard26]

I honestly don't know why we specify setuptools-scm in both place, but given pyproject.toml is the newer standard (also isn't setuptools specific) it's probably best to pin there (although setup.cfg is by no means deprecated or anything like that). FYI looks like you got some trailing whitespace in setup.cfg. A comment explaining why we're pinning would be fantastic too but totally not neccesary.

[ichard26]

Sorry @FabianNiehaus but I ended up incorporating your PR into a new one with some tweaks applied on top since I need to get a release out today. I hope the credit via the co-author line is good enough! Thanks for your contributing! Feedback welcome to #2238 :3