chore(deps): update postgres docker tag to v18

compose.discord.yml

@@ -30,7 +30,7 @@ services:
       - internal
 
   discorddb:
-    image: postgres:13-alpine
+    image: postgres:18-alpine
     secrets:
       - discord_db_password
     environment:

compose.signal.yml

@@ -35,7 +35,7 @@ services:
       - internal
 
   signaldb:
-    image: postgres:13-alpine
+    image: postgres:18-alpine
     secrets:
       - signal_db_password
     environment:

compose.telegram.yml

@@ -40,7 +40,7 @@ services:
       - internal
 
   telegramdb:
-    image: postgres:13-alpine
+    image: postgres:18-alpine
     secrets:
       - telegram_db_password
     environment: