Support proxy domain validation for Garage web domains

Also rename the data bag item

data_bags/credentials/gandi_api.json

@@ -0,0 +1,24 @@
+{
+  "id": "gandi_api",
+  "key": {
+    "encrypted_data": "d3/rJMX6B9GuzUt0/mIk/lgQ3qGyQdbNXH6UEm3ZX7DeSl+rbW9FPJCRWg==\n",
+    "iv": "15YVAYla7PqqVOab\n",
+    "auth_tag": "xQSq+ld6SDOAER07N4ZkUQ==\n",
+    "version": 3,
+    "cipher": "aes-256-gcm"
+  },
+  "access_token": {
+    "encrypted_data": "geQwcNosiJZmqbbMpD/I+a2yueBzpV6C8Rb7vrCD8kR161ZRjvqLe+g/1XpT\n2/65wKYDMTrdto1I030=\n",
+    "iv": "1sj58eyooOZ8FTYn\n",
+    "auth_tag": "yBNfgWXaToc06VDLly/HUw==\n",
+    "version": 3,
+    "cipher": "aes-256-gcm"
+  },
+  "domains": {
+    "encrypted_data": "p5rIQTyCE+0d4HIuA4GKEAFekh7qEC4xe9Rm/kP0DyzY83FO0/4uKIvYoZRB\n",
+    "iv": "LWlx98NSS1/ngCH1\n",
+    "auth_tag": "FID+x/LjTZ3cgQV5U2xZLA==\n",
+    "version": 3,
+    "cipher": "aes-256-gcm"
+  }
+}

data_bags/credentials/gandi_api_5apps.json

@@ -1,17 +0,0 @@
-{
-  "id": "gandi_api_5apps",
-  "key": {
-    "encrypted_data": "AGYIkLdbnU3+O6OxGsFyLpZtTw531s2dbRC4Lik+8NYp3l4P0UMM2Pqf0g==\n",
-    "iv": "kPRHGpLwNIC3MpES\n",
-    "auth_tag": "wKth2tA+JxILFIKppHLDJg==\n",
-    "version": 3,
-    "cipher": "aes-256-gcm"
-  },
-  "access_token": {
-    "encrypted_data": "+tKKFcWV0CZ5wEB/No5hou5+p1llsUkq7AXBvfnA7xsgbpa2q8AX/2UFf9Cf\nGtd9om1CeJJtz+o4ceA=\n",
-    "iv": "hLJSV77DQtqXZDbV\n",
-    "auth_tag": "8xgyudyDk4hq16LRkykGhQ==\n",
-    "version": 3,
-    "cipher": "aes-256-gcm"
-  }
-}