Maybe consider pinning dependencies to avoid CI failures

[shenxianpeng]

After #337 was merged into the main branch, I noticed that the CI failed again. related issue: theacodes/cmarkgfm#84

A similar problem occurred earlier when upgrading docutils (see #333 (comment)).

It might help to pin these dependencies to specific versions and let Dependabot handle version bumps (PR has been created #338). That would make it easier to trace which dependency update causes CI failures.

Relevant lines:

readme_renderer/pyproject.toml

Line 40 in ef173c2

md = ["cmarkgfm>=0.8.0"]

readme_renderer/pyproject.toml

Lines 11 to 15 in ef173c2

	dependencies = [
	"nh3>=0.2.14",
	"docutils>=0.21.2",
	"Pygments>=2.5.1",
	]