Remove no-longer-needed variant expected regression result files.

numerology_1.out and float8-small-is-zero_1.out differ from their
base files only in showing plain zero rather than minus zero for
some results.  I believe that in the wake of commit 6eb3eb5,
we will print minus zero as such on all IEEE-float platforms
(and non-IEEE floats are going to cause many more regression diffs
than this, anyway).  Hence we should be able to remove these and
eliminate a bit of maintenance pain.  Let's see if the buildfarm
agrees.

Discussion: https://postgr.es/m/29037.1539021687@sss.pgh.pa.us

Author: tglsfdc