docs: change email address mentions to depot@tvl.su

This is the new address which leads to the public inbox at inbox.tvl.su

Change-Id: I45d98a373b8acda49b05c4f74669ffb9ad1f1a3c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7632
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>

ops/keycloak/main.tf

@@ -37,7 +37,7 @@ resource "keycloak_realm" "tvl" {
     from_display_name = "The Virus Lounge"
     host              = "127.0.0.1"
     port              = "25"
-    reply_to          = "depot@tazj.in"
+    reply_to          = "depot@tvl.su"
     ssl               = false
     starttls          = false
   }