fix(test-harness): add external references validation scenario for OAS 3.1

Author: fluz

…rios/oas3.1/external-references.scenario …s/scenarios/oas3.1/external-ref.scenariotest-harness/scenarios/oas3.1/external-references.scenario renamed to test-harness/scenarios/oas3.1/external-ref.scenario test-harness/scenarios/oas3.1/external-references.scenario renamed to test-harness/scenarios/oas3.1/external-ref.scenario

@@ -8,7 +8,7 @@ info:
   description: Example API description
 paths:
   /greetings:
-    $ref: "{asset:greetings.yaml}"
+    $ref: "greetings.yaml"
 tags:
   - name: User
     description: Info about users
@@ -35,6 +35,6 @@ extends: [[spectral:oas, off]]
 rules:
   oas3-schema: error
 ====command====
-{bin} lint {document} --ruleset {asset:ruleset.yaml} --resolve
-====expected-stdout====
+{bin} lint {document} --ruleset {asset:ruleset.yaml}
+====stdout====
 No results with a severity of 'error' found!