build: override bundled libsemigroups install paths

[jengelh]

Fixes: #1073

[james-d-mitchell]

Thanks for the PR @jengelh, the "with-external-libsemigroups" is expected to fail at the moment, but not the Cygwin job, any chance you could adapt the changes in this PR so that the Cygwin job also passes? Thanks!

[jengelh]

cygwin x64

Now running tests from tst/teststandard.g
Error, Variable: 'SemigroupsTestInstall' must have a value
Error: Process completed with exit code 1.

That does not look like dll related things (or if, it's not very indicative).

[james-d-mitchell]

It states just above this that the kernel module isn't compiled, I guess it is unable to find the DLL, which would be related to your changes I think

[james-d-mitchell]

Just rebased onto main, let's see if the ci passes.

[james-d-mitchell]

@jengelh the cygwin job still fails, I'm afraid. @Joseph-Edwards any chance you can take a look at this in the meeting tomorrow?

[Joseph-Edwards]

@Joseph-Edwards any chance you can take a look at this in the meeting tomorrow?

Will do

[james-d-mitchell]

@jengelh the changes in my commit here fix the ci, can you please confirm whether or not the changes we've reverted were not essential to your pr? I.e. does the pr as given resolve the issue?