fixes an issue with symbols in compset names on derecho

[jedwards4b]

Description of changes

Fixes an issue when running create_test with a full compset name that contains special characters like %.

Specific notes

I changed the call to the Makefile from buildexe to use a relative path instead of full path, this seems to
have addressed the issue.

Contributors other than yourself, if any:

CMEPS Issues Fixed (include github issue #):

Are changes expected to change answers? (specify if bfb, different at roundoff, more substantial)

Any User Interface Changes (namelist or namelist defaults changes)?

Testing performed

Please describe the tests along with the target model and machine(s)
If possible, please also added hashes that were used in the testing

[briandobbins]

It's odd that we don't know the direct connection with GNU make and special characters (I still suspect the locale settings), but if this works in practice, passing our tests, that works for me.