tests: Add `rhg` and `no-rhg` for #require and #if in .t files...
tests: Add `rhg` and `no-rhg` for #require and #if in .t files
With this we can allow some small differences in expected output
between Rust-based and Python-based code paths.
Differential Revision:
https://phab.mercurial-scm.org/D10096
