Remove AWS ECR and their CI publication workflow

We no longer deploy images published to AWS ECR.
Remove the repositories and the associated CI workflows.

All their existing users should use GitHub Container Registry instead.

deploy/infrastructure/common/ecr.tf

@@ -1,18 +1,6 @@
 module "ecr_ue2" {
   source = "../modules/ecr"
 
-  repositories = [
-    "storetheindex/storetheindex",
-    "index-observer/index-observer",
-    "index-provider/index-provider",
-    "indexstar/indexstar",
-    "ipni/heyfil",
-    "ipni/dhstore",
-    "ipni/caskadht",
-    "ipni/dhfind",
-    "ipni/lookout",
-    "ipni/cassette",
-    "ipni/telemetry",
-  ]
+  repositories = []
   tags = local.tags
 }