Drop some needles that became unused with recent Vault change

Signed-off-by: Adam Williamson <awilliam@redhat.com>

needles/kde/apps/vault/vault_backend_available-cryfs-20220303.json

@@ -1,15 +0,0 @@
-{
-  "area": [
-    {
-      "xpos": 203,
-      "width": 103,
-      "type": "match",
-      "height": 20,
-      "ypos": 183
-    }
-  ],
-  "properties": [],
-  "tags": [
-    "vault_backend_available"
-  ]
-}

needles/kde/apps/vault/vault_backend_available-encfs-20240720.json

@@ -1,15 +0,0 @@
-{
-  "area": [
-    {
-      "height": 20,
-      "width": 103,
-      "xpos": 202,
-      "ypos": 181,
-      "type": "match"
-    }
-  ],
-  "properties": [],
-  "tags": [
-    "vault_backend_available"
-  ]
-}