CI‌ generated package artifacts aren't usable like regular dist builds

[alerque]

Not sure what's up, but the Github Actions artifact zip, which should be an archive of make distdir is not quite that.

1. It has a ready to run configure script but it isn't marked as executable.
2. The file aclocal-1.15 and some friends are missing, requiring an autoreconf run which shouldn't be necessary.
3. It doesn't have a lua_modules_dist directory. This might be desirable actually, but it was unexpected because the dist package should have it.

[alerque]

This is because we've been abusing automake (knowingly in my case). It isn't supposed to let you have dynamically generated distribution file lists.

One of many:

extra_dist = $(shell find lua_modules_dist -type f -print 2>/dev/null ||:)

We get away with cheating on this rule most of the time, but opens us up to all sorts of race conditions. See Why doesn't Automake support wildcards?

[alerque]

Point 1 here is an upstream Github bug. All the others I've dealt with.

[alerque]

If this is a problem for anybody it looks like the solution is to zip up a zip. I mostly use the artifacts to check how the PDFs of the manual and examples came out and do file listings to see what is there. I don't care about actually compiling it very much. If anybody does (before Github fixes this bug) we need to switch to posting double zipped artifacts.