Backport PR #29827 on branch v3.10.x (TST: Remove unnecessary test images)

[QuLogic]

PR summary

Note that I only backported the first commit of #29827; I don't think it makes sense to make the API change of check_figures_equal defaults in a bug fix release.

PR checklist

• [n/a] "closes #0000" is in the body of the PR description to link the related issue
• new and changed code is tested
• [n/a] Plotting related features are demonstrated in an example
• [n/a] New Features and API Changes are noted with a directive and release note
• [n/a] Documentation complies with general and docstring guidelines

[dstansby]

A rebase should fix the doc build, if this is something we still want to backport.

[dstansby]

I've rebased on to the latest v3.10.x

[ksunden]

Rerunning failed Azure Linux checks. They were all timeout errors, not image test errors, so probably unrelated to the changes here, but there were 9 failures, which is more than we usually see for stochastic failures. And it was on Linux where the vast majority of such timeout problems are on Windows for us.

I'll be satisfied if they pass, will re-evaluate if they fail.

[ksunden]

Hmmm... seems like we are continuing to get failures on the Azure Linux 3.11 build...

However, does not appear to be unique to this PR upon closer look at recent backports, so willing to merge over.