Don't change directories when cloning a repo

[amalloy]

This was making it impossible to pin to a specific commit when using relative file paths as repo URLs.

Please include the following checklist in your PR:

• Any changes that could be relevant to users have been recorded in the ChangeLog.md
• The documentation has been updated, if necessary.

I tested this change by running stack test three times:

1. Before I made any changes, tests pass
2. After intentionally implementing my change incorrectly, tests fail
3. After a correct implementation of my change, tests pass again

[amalloy]

I've included a Changelog update in what I think was the right place, and I believe no documentation update is necessary (already-documented behavior now works better).

[snoyberg]

In addition to the inline comments:

1. I see that there's a CI failure from the style checker
2. It may make sense to PR this against the stable branch instead of master

[snoyberg]

This should go in "unreleased changes" instead. It should also likely be mentioned in the pantry changelog.

[snoyberg]

Please add a comment that this is intentionally not run within the withWorkingDir below in order to allow relative paths to work.

[amalloy]

The hlint failure was on unmodified code in a different file; I'm not inclined to touch that as part of this PR.

I've adjusted the target branch, and made the changes you requested, except: the pantry changelog appears to currently be empty, after a year's worth of commits to it. Do you want this to be the first change documented therein?

[snoyberg]

the pantry changelog appears to currently be empty, after a year's worth of commits to it

Right, that's intended: pantry has been in development for a year, but only last week had its first release. This is the first actual change versus a released version.

[amalloy]

Done.

[snoyberg]

LGTM. I've merged in the changes on stable so CI will pass. This is good to merge once CI goes green.