beta: compile texvc on both datacenters

Creates jobs:
 beta-recompile-math-texvc-eqiad
 beta-recompile-math-texvc-pmtpa

No functional changes with the beta-recompile-math-texvc job beside
assigning the label to tie each job to a different bastion.

Change-Id: I09424ed3bf4c2d0d5bda49959dedfe43b43b837e