ci-make improvements

[pflanze]

Some small changes for once.

Allow to easily inspect the outputs especially of "make ci", i.e. when successful runs are not shown on stdout.

[yusufraji]

ci-make: avoid treating input as test commands

Thanks to shellcheck.

I didn't experience any difference before and after the commit. I think I'm missing something.
And What's spellcheck?

[pflanze]

BTW note that ci-make leaks the temp files. It does so on purpose, exactly so that one can go and inspect them afterwards. On GitHub CI the whole context is deleted after a CI run so the files will be gone anyway, and on our local laptops they are just too small to worry about, even if they are only cleaned away on reboot (rebooting once in 6 months when using ci-make 10 times per day on average while producing 20 KB per each run like in this project generates 36 MB of waste, which occupies disk space with a value of (with 200 EUR for a 3.6 TB disk) 0.2 cent). (Why am I even doing this calculation? It used to be that 36 MB was an impossible amount to store on a computer I owned...)