run-tests: fix conditional when tests are run outside of `tests`
The logic to find `hghave` was using `__file__` but… non absolute path in
`__file__` gets wrong as soon as we change directory (thanks python… you are
being helpful). The rest of the `run-tests.py` code already deal with this
fine. We simply reuse the `RUNTESTDIR` variable to fix it.
public attribute not declared in interfaces: badpeer.badattribute
public attribute not declared in interfaces: badpeer.badmethod