1. The `--json` export now only renders the `login` field for User types
and `name` and `slug` fields for Team types.
2. The `pr view` command now renders team reviewers in the format of
`ORG/SLUG` instead of the team name. This is so that the same value
can be used in the `pr create -r` flag.
This removes sensitivity to the BROWSER environment variable in tests
and makes it easier to verify the URL that the browser was invoked with
without having to stub sub-processes.
For asserting command output, exact string matches are preferred in most cases. In cases when a pattern match is needed, the test can use regexp ad hoc.
If the `--repo` flag is specified, then the user intends to select a
repository other than the current one. In that case, it doesn't make
sense to fall back to detecting the PR belonging to the current branch,
so throw a descriptive error instead.
