Merge pull request #35265 from hashicorp/b-aws_mq_broker.resourceUserHash-panic

r/aws_mq_broker: Fix v5.32.0 regression panic `interface conversion: interface {} is *schema.Set, not []string`

Author: ewbankkit

.changelog/35265.txt

@@ -0,0 +1,3 @@
+```release-note:enhancement
+resource/aws_mq_broker: Fix `interface conversion: interface {} is *schema.Set, not []string` panic
+```

internal/service/mq/broker.go

@@ -746,7 +746,7 @@ func resourceUserHash(v interface{}) int {
 		buf.WriteString("false-")
 	}
 	if g, ok := m["groups"]; ok {
-		buf.WriteString(fmt.Sprintf("%v-", g.([]string)))
+		buf.WriteString(fmt.Sprintf("%v-", g.(*schema.Set).List()))
 	}
 	if p, ok := m["password"]; ok {
 		buf.WriteString(fmt.Sprintf("%s-", p.(string)))
@@ -999,7 +999,7 @@ func flattenUsers(users []*types.User, cfgUsers []interface{}) *schema.Set {
 			m["replication_user"] = aws.ToBool(u.ReplicationUser)
 		}
 		if len(u.Groups) > 0 {
-			m["groups"] = u.Groups
+			m["groups"] = flex.FlattenStringValueSet(u.Groups)
 		}
 		out = append(out, m)
 	}