Add a test for shelving location circ limit set

[Jane Sandberg]

I was barking up the wrong tree on a different bug, and while investigating, I wrote a pgtap test that exercises the circ limit set for shelving locations. Offering it as a PR here, since it helps to get more of the system under test.

[Jane Sandberg (sandbergja)]

Here is the branch: https://git.evergreen-ils.org/?p=working/Evergreen.git;a=shortlog;h=refs/heads/user/sandbergja/lp2048425-shelving-location-circ-limit-set

[Galen Charlton (gmc)]

Tested and signed off: working/user/gmcharlt/lp2048425_signoff