replace "nosysroot" with a "noabi" env

[beckermr]

Due to the fact that Rubin has to maintain its own ABIs outside of conda-forge, there are certain packages (like the compilers, openblas/mkl, etc) that receive extra pins beyond the default conda-forge pins.

My proposal is to separate out those pins like we separated out the sysroot pin to cos7. This will allow for stackvana builds to use the conda-forge mechanisms properly while not breaking builds outside of conda-forge.

Cc @ktlim @erykoff

[beckermr]

Specifically we’d have a rubin-env-abi package that would hold certain compiler, sysroot, openmp, blas, and other core pins. The main distinguishing factor for putting pins there would be how far towards the bottom they are and if they are needed for conda-forge builds or not.