Corrected remote document lookup behavior

When remote documents are requested and there is no way to know the base URL, the index will now try and determine the base path from the way the spec was loaded (if it comes in remote, we use the base URL of the spec)

document_test.go

@@ -504,6 +504,35 @@ paths:
 
 	assert.Equal(t, d, strings.TrimSpace(string(rend)))
 }
+
+func TestDocument_RemoteWithoutBaseURL(t *testing.T) {
+
+	// This test will push the index to do try and locate remote references that use relative references
+	spec := `openapi: 3.0.2
+info:
+  title: Test
+  version: 1.0.0
+paths:
+  /test:
+    get:
+      parameters:
+        - $ref: "https://schemas.opengis.net/ogcapi/features/part2/1.0/openapi/ogcapi-features-2.yaml#/components/parameters/crs"`
+
+	config := datamodel.NewOpenDocumentConfiguration()
+
+	doc, err := NewDocumentWithConfiguration([]byte(spec), config)
+	if err != nil {
+		panic(err)
+	}
+
+	result, errs := doc.BuildV3Model()
+	if len(errs) > 0 {
+		panic(errs)
+	}
+
+	assert.Equal(t, "crs", result.Model.Paths.PathItems["/test"].Get.Parameters[0].Name)
+}
+
 func TestDocument_ExampleMap(t *testing.T) {
 	var d = `openapi: "3.1"
 components: