Database: duplicate key value violates unique constraint "cache_data_pkey"

### What happened? Im running a single grafana container(`v12.0.1 (80658a73c5)`) together with a postgres container(`postgres (PostgreSQL) 16.9 (Debian 16.9-1.pgdg120+1)`) for its database. The postgres-database was migrated from sqlite a few months ago. The postgres container is throwing errors every few minutes: ``` 2025-05-27 09:57:36.862 CEST [29764] STATEMENT: INSERT INTO cache_data (cache_key,data,created_at,expires) VALUES($1,$2,$3,$4) 2025-05-27 09:57:36.877 CEST [29765] ERROR: duplicate key value violates unique constraint "cache_data_pkey" 2025-05-27 09:57:36.877 CEST [29765] DETAIL: Key (cache_key)=(authn-proxy-sync-ttl:YYY) already exists. 2025-05-27 09:57:36.877 CEST [29765] STATEMENT: INSERT INTO cache_data (cache_key,data,created_at,expires) VALUES($1,$2,$3,$4) 2025-05-27 09:57:36.880 CEST [29765] ERROR: duplicate key value violates unique constraint "cache_data_pkey" 2025-05-27 09:57:36.880 CEST [29765] DETAIL: Key (cache_key)=(authn-proxy-sync-ttl:YYY) already exists. 2025-05-27 09:57:36.880 CEST [29765] STATEMENT: INSERT INTO cache_data (cache_key,data,created_at,expires) VALUES($1,$2,$3,$4) 2025-05-27 09:57:48.992 CEST [29767] ERROR: duplicate key value violates unique constraint "cache_data_pkey" 2025-05-27 09:57:48.992 CEST [29767] DETAIL: Key (cache_key)=(authinfo-0-authproxy-XXX) already exists. 2025-05-27 09:57:48.992 CEST [29767] STATEMENT: INSERT INTO cache_data (cache_key,data,created_at,expires) VALUES($1,$2,$3,$4) 2025-05-27 09:57:49.007 CEST [29765] ERROR: duplicate key value violates unique constraint "cache_data_pkey" 2025-05-27 09:57:49.007 CEST [29765] DETAIL: Key (cache_key)=(authn-proxy-sync-ttl:XXX) already exists. 2025-05-27 09:57:49.007 CEST [29765] STATEMENT: INSERT INTO cache_data (cache_key,data,created_at,expires) VALUES($1,$2,$3,$4) 2025-05-27 09:57:49.010 CEST [29765] ERROR: duplicate key value violates unique constraint "cache_data_pkey" 2025-05-27 09:57:49.010 CEST [29765] DETAIL: Key (cache_key)=(authn-p…