rhg: use a release-mode executable in tests
This allows the rhg build for test-rhg.t to share compiled dependencies
such as hg-core with the hg-cpython build for other tests.
For context, my wrapper script for the typical edit-compile-test
cycle now looks like this:
(cd rust && cargo +nightly-2020-10-04 fmt)
(cd rust && cargo build --release -p rhg)
make --silent local PURE=--rust
python test/run-tests.py --local "$@"
Differential Revision: https://phab.mercurial-scm.org/D9728
$ hg init
$ echo a > a
$ hg ci -Am t
adding a
$ hg mv a b
$ hg ci -Am t1
$ hg debugrename b
b renamed from a:b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3
$ hg mv b a
$ hg ci -Am t2
$ hg debugrename a
a renamed from b:37d9b5d994eab34eda9c16b195ace52c7b129980
$ hg debugrename --rev 1 b
b renamed from a:b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3