Vision quickstart spec: added better description

Author: Frank Natividad

vision/spec/quickstart_spec.rb

@@ -17,7 +17,7 @@
 
 describe "Vision Quickstart" do
 
-  it "label a cat image" do
+  it "performs label a sample image file" do
     gcloud = Google::Cloud.new ENV["GOOGLE_CLOUD_PROJECT"]
 
     expect(Google::Cloud).to receive(:new).with("YOUR_PROJECT_ID").