Fixes exception shouldn't be thrown when casting
`Orchestra\Support\Collection` to CSV when no data is available.

Signed-off-by: crynobone <crynobone@gmail.com>
Merge branch '2.1' into 2.2
Fixes missing abstract class causing the testcase to fail.

Signed-off-by: crynobone <crynobone@gmail.com>
Update changelog

Signed-off-by: crynobone <crynobone@gmail.com>
Merge branch '2.2'