Remove hardcoded build paths & modify basic workflow to build in random path

[iyanmv]

This fixes #2018 using helpers.get_current_build_dir_name()

In addition, the basic workflow is modified to use a random build path. Hopefully, this small change will catch future changes that introduce hardcoded paths.

• Does this PR change the input/output behaviour of a cryptographic algorithm (i.e., does it change known answer test values)? (If so, a version bump will be required from x.y.z to x.(y+1).0.)
• Does this PR change the list of algorithms available -- either adding, removing, or renaming? Does this PR otherwise change an API? (If so, PRs in fully supported downstream projects dependent on these, i.e., oqs-provider will also need to be ready for review and merge by the time this is merged.)

[SWilson4]

Thanks for the fix!

[iyanmv]

I pushed too quick before catching the train 😅 I will fix the env name in a bit, and test locally the pipeline before pushing again.

[bhess]

Thanks for this fix @iyanmv. See the comments below, otherwise LGTM.

[iyanmv]

I put back the . (replacing the .. instead of nothing) at the end of each cmake command.