Restrict setuptools version in CI workflow

[alexanderwerning]

pkg_resources was removed in setuptools 82, but sacred depends on it.
For more information see: pypa/setuptools#5174

[Copilot]

Pull request overview

This PR aims to keep CI green by preventing setuptools upgrades that remove pkg_resources (which is still required by the sacred dependency used in the repo’s [all]/test extras).

Changes:

• Pin setuptools to a fixed version during CI dependency installation.
• Remove the Ubuntu 22.04 / Python 3.7 CI job from the test matrix.
• Stabilize a to_list doctest output by forcing np.int64 dtype.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
.github/workflows/tests.yml	Pins setuptools in the CI install step and adjusts the OS/Python matrix (dropping 3.7/ubuntu-22.04).
padertorch/utils.py	Adjusts a doctest to explicitly use np.int64 for consistent pretty-printed output.

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[Copilot]

Pinning to an exact setuptools==75.3.4 is more restrictive than necessary for the stated issue (pkg_resources removal in setuptools 82) and may require extra maintenance. Consider using a bounded constraint (e.g., <82) and/or adding an inline comment explaining the pin so it's clear when/why it can be relaxed.

Suggested change

	python -m pip install --upgrade pip setuptools==75.3.4 wheel
	# Pin setuptools below 82 to avoid pkg_resources removal; keep minimum at 75.3.4 for compatibility.
	python -m pip install --upgrade pip "setuptools>=75.3.4,<82" wheel

[Copilot]

This hunk removes the Ubuntu 22.04 / Python 3.7 job, which (a) changes CI coverage and (b) leaves a now-dead reference to ubuntu-22.04 later in the workflow (Install linux dependencies uses if: ... || matrix.os == 'ubuntu-22.04'). If dropping 3.7/22.04 is intended, please also update the later if condition accordingly (and consider noting the coverage change in the PR description).