[DOCS]: Remove or rewrite Buildspec tutorial test

[Mendi03]

Documentation Link

https://buildtest.readthedocs.io/en/devel/buildspecs/spack.html#install-specs

Issue Description

There is a test failure when running the buildtest build -b /home/spack/buildtest/examples/spack/install_specs.yml and the
buildtest inspect query -o --testpath install_specs_example clone_spack_and_install_zlib commands found in the Buildtest Spack Integration Tutorials of the docs.

• This test needs to be rewritten or removed since there shouldn’t be a test failure.

Output of buildtest build -b /home/spack/buildtest/examples/spack/install_specs.yml

Output of buildtest inspect query -o --testpath install_specs_example clone_spack_and_install_zlib

Notes:

• It is possible this could also fix the issue found in [DOCS]: Build Failure in Buildspec tutorial for zlib #1518
• See this discussion for when the issue was found.

Post question in Slack

• I agree that I posted my question in slack before creating this issue

Is there an existing issue

• I confirm there is no existing issue for this issue