Moved certrbot plugin list to backend

frontend doesn't include when building in react version
adds swagger for existing dns-providers endpoint

backend/schema/paths/nginx/certificates/test-http/post.json

@@ -7,18 +7,24 @@
 			"BearerAuth": ["certificates"]
 		}
 	],
-	"parameters": [
-		{
-			"in": "query",
-			"name": "domains",
-			"description": "Expansions",
-			"required": true,
-			"schema": {
-				"type": "string",
-				"example": "[\"test.example.ord\",\"test.example.com\",\"nonexistent.example.com\"]"
+	"requestBody": {
+		"description": "Test Payload",
+		"required": true,
+		"content": {
+			"application/json": {
+				"schema": {
+					"type": "object",
+					"additionalProperties": false,
+					"required": ["domains"],
+					"properties": {
+						"domains": {
+							"$ref": "../../../../common.json#/properties/domain_names"
+						}
+					}
+				}
 			}
 		}
-	],
+	},
 	"responses": {
 		"200": {
 			"description": "200 response",