Script contents should URL quoted

[Victor]

    def run_script(self, script):
        return self.jenkins_open(Request(self._build_url(SCRIPT_TEXT),
                                         "script=".encode('utf-8') + script.encode('utf-8')))

If script contains '&' symbol, the server receives split strings -- garbage.
The code should be URL quoted in the URL.

[Khai Do (zaro0508)]

I believe this is fixed with change https://review.openstack.org/#/c/407479/