DB migration failure when updating to 7.4.x

Hello,

We see the following error when upgrading from Grafana 7.3.7 to 7.4.x (we tried 7.4.0, 7.4.1. and 7.4.2). Has anyone else also experienced this error?

t=2021-02-23T17:16:54+0000 lvl=info msg="Starting DB migrations" logger=migrator
t=2021-02-23T17:16:55+0000 lvl=info msg="Executing migration" logger=migrator id="drop index UQE_alert_rule_tag_alert_id_tag_id - v1"
t=2021-02-23T17:16:55+0000 lvl=eror msg="Executing migration failed" logger=migrator id="drop index UQE_alert_rule_tag_alert_id_tag_id - v1" error="pq: cannot drop index \"UQE_alert_rule_tag_alert
_id_tag_id\" because constraint UQE_alert_rule_tag_alert_id_tag_id on table alert_rule_tag requires it"
t=2021-02-23T17:16:55+0000 lvl=eror msg="Exec failed" logger=migrator error="pq: cannot drop index \"UQE_alert_rule_tag_alert_id_tag_id\" because constraint UQE_alert_rule_tag_alert_id_tag_id on t
able alert_rule_tag requires it" sql="DROP INDEX \"UQE_alert_rule_tag_alert_id_tag_id\" CASCADE"
service init failed: migration failed: pq: current transaction is aborted, commands ignored until end of transaction block

yes, upgrade is not possible.

We had another instance we were able to upgrade successfully. Is there a way we can perform the psql commands needed for the migration?