sql: wrong error code returned when performing invalid byte sequence casts

[asubiotto]

These were found running the https://github.com/lib/pq test suite against cockroach. Specifically TestBinaryByteSlicetoUUID fails because an error with the Syntax error code is returned rather than the expected CharacterNotInRepertoire code (postgres does this). TestBinaryByteSliceToInt is also expected to fail with the same error code but returns a ProtocolViolation error seemingly further up the stack. The latter deserves some more investigation.

We should also sanity check other cases in which we return Syntax error codes when parsing strings (e.g. string as decimal).

Jira issue: CRDB-5437

[github-actions]

We have marked this issue as stale because it has been inactive for
18 months. If this issue is still relevant, removing the stale label
or adding a comment will keep it active. Otherwise, we'll close it in
5 days to keep the issue queue tidy. Thank you for your contribution
to CockroachDB!

[github-actions]

We have marked this issue as stale because it has been inactive for
18 months. If this issue is still relevant, removing the stale label
or adding a comment will keep it active. Otherwise, we'll close it in
10 days to keep the issue queue tidy. Thank you for your contribution
to CockroachDB!