Update SXG Origin Trial Token on HTTP Gateway (II)

[lidel]

This is continuation of #453 and ipfs/in-web-browsers#121

I renewed our participation again, this time until Mar 2, 2019, but we need to update Origin-Trial header to new value:

Aj+La2UsIB9Nh7WeJGdAUQZ4WaJ0EMw3y0DySewSkrNU4xvsQhUiNQ34aYv+dYFn5Rd7L0Yc7KF1N1N77D9a5woAAABeeyJvcmlnaW4iOiJodHRwczovL2lwZnMuaW86NDQzIiwiZmVhdHVyZSI6IlNpZ25lZEhUVFBFeGNoYW5nZU9yaWdpblRyaWFsIiwiZXhwaXJ5IjoxNTUxNTU2OTg5fQ==

Note: this is time-sensitive (cc @kyledrake), as the old one will expire on Jan 25th.

References

• [Meta] Signed HTTP Exchanges and WebPackage
• Signed HTTP Exchanges: Chrome Origin Trials (living document)
• Origin Trial Token Validator (to ensure token is correct and did not expire yet)