rspec extension specs don't clean up after themselves

[kytrinyx]

The tests in spec/extensions/rspec_approvals_spec.rb lines 64 - 78 leave the *received.txt files even when the tests pass. They also add entries in the .approvals file.

This gets in the way when there are other failures and you're using the command line tool to step through each of the diffs one at a time.

$ cat .approvals 
spec/fixtures/approvals/verifies_a_failure.approved.txt spec/fixtures/approvals/verifies_a_failure.received.txt
spec/fixtures/approvals/verifies_a_failure_diff.approved.txt spec/fixtures/approvals/verifies_a_failure_diff.received.txt
spec/fixtures/approvals/verifies_directory/a_failure.approved.txt spec/fixtures/approvals/verifies_directory/a_failure.received.txt
spec/fixtures/approvals/verifies_directory/a_failure_diff.approved.txt spec/fixtures/approvals/verifies_directory/a_failure_diff.received.txt