tests: Add more tests around exception handling.
tests: Add more tests around exception handling.

This verifies that we actually do enqueue a record when there is an
error on non-staging.  With the previous commit, it verifies that that
data serializes correctly.

andersk/zulip,punchagan/zulip,eeshangarg/zulip,showell/zulip,kou/zulip,hackerkid/zulip,kou/zulip,zulip/zulip,zulip/zulip,kou/zulip,eeshangarg/zulip,kou/zulip,andersk/zulip,eeshangarg/zulip,eeshangarg/zulip,rht/zulip,andersk/zulip,showell/zulip,hackerkid/zulip,showell/zulip,showell/zulip,hackerkid/zulip,punchagan/zulip,punchagan/zulip,zulip/zulip,zulip/zulip,rht/zulip,rht/zulip,rht/zulip,hackerkid/zulip,kou/zulip,andersk/zulip,punchagan/zulip,rht/zulip,hackerkid/zulip,rht/zulip,punchagan/zulip,zulip/zulip,punchagan/zulip,kou/zulip,kou/zulip,andersk/zulip,andersk/zulip,zulip/zulip,eeshangarg/zulip,showell/zulip,punchagan/zulip,eeshangarg/zulip,hackerkid/zulip,showell/zulip,andersk/zulip,hackerkid/zulip,rht/zulip,zulip/zulip,showell/zulip,eeshangarg/zulip