Update jsonschema and pipeline linting

.woodpecker/test.yml

@@ -19,6 +19,7 @@ pipeline:
     when:
       path:
         - ".woodpecker/**"
+        - "pipeline/schema/**"
 
   vendor:
     image: *golang_image

pipeline/schema/schema.json

@@ -364,7 +364,12 @@
         "ports": {
           "description": "expose ports to which other steps can connect to",
           "type": "array",
-          "items": { "type": "number" },
+          "items": {
+            "oneOf": [
+              { "type": "number" },
+              { "type": "string" }
+            ]
+          },
           "minLength": 1
         }
       }