add testcase for failing export for trusted key

test/cfa/ntp_conf_test.rb

@@ -449,4 +449,12 @@ def ntp_conf(file)
 
     expect(file.content.lines).to include("trustedkey 1# path to keys file\n")
   end
+
+  it "loads properly when it is defined in file" do
+    file.content << "##stefanmurks\ntrustedkey 1\n"
+    ntp.load
+
+    trustedkey = ntp.records.last
+    expect(trustedkey.value).to eq "1"
+  end
 end