Snowflake updating existing constraints with set_rely_norely seems to have gone AWOL

[mgt-pexa]

Commit f60652b seems to have removed the set_rely_norely update for constraints passing / failing tests.

Seems to be impacting 1.0.5 onwards.

Just in case no one else noticed.

[mgt-pexa]

Specifically, if the constraint already exists, dbt-constraints will not change the rely / norely flag on the constraint to match the current test results.
ie.
first run / build of an incremental model has unique test success so the constraint is created as "RELY"
second run / build of the model fails the unique test and the constraint is not updated to "NORELY", as the macro ignores "pre-existing" constraints.
This is inconsistent with pre 1.0.5 dbt-constraints.