Run tests on CI (not under crippled)

[yarikoptic]

There is https://github.com/datalad/datalad-catalog/blob/main/.appveyor.yml but I do not think that testing is enabled for anyone on appveyor, and thus PRs lack tests running. There is only a run under crippled fs , but they were Red for the past two months and nobody looked in them and it could be upstream issue etc. So before tackling those, runs under normal conditions should be established.
IMHO

• @mih should add to his pool of "paid appveyor tests"
• I will propose a workflow on github but not under crippled so we have consistent environment changing only in cripppled-vs-not

[jsheunis]

Update: #213 (comment)

[jsheunis]

Updated revert-PR with more commits: #223

[jsheunis]

Moved issue content to datalad-extension-template repo for further evaluation. Closing here.