Fix for ESMF link path

[abishekg7]

This PR addresses the linking error that arises when building the MPAS atmosphere core with the nvhpc compiler in DEBUG mode.

The incorrect make variable MPAS_ESMF_LIBS with MPAS_ESMF_LIB, which is the variable defined in the root Makefile.

[danrosen25]

@abishekg7 Sorry for the typo! I looked through my work and I think that you caught the only place MPAS_ESMF_LIBS was used. NCAR CISL is working on some CI infrastructure so we'll see less of these mistakes in the future.
66517f6

[mgduda]

@abishekg7 Sorry for the typo! I looked through my work and I think that you caught the only place MPAS_ESMF_LIBS was used. NCAR CISL is working on some CI infrastructure so we'll see less of these mistakes in the future. 66517f6

In principle, I don't think the build_tables executable should even need the ESMF library, but it seems that the NVHPC linker requires the ESMF library when compiling with certain debug options. So the typo in the name of the MPAS_ESMF_LIB variable is something that would probably have only tripped up the NVHPC debug builds, but otherwise doesn't impact the correctness of essentially any other build.