update relayhub singleton address

contracts/gsn/GSNContext.sol

@@ -18,7 +18,7 @@ contract GSNContext is Context {
     event RelayHubChanged(address indexed oldRelayHub, address indexed newRelayHub);
 
     constructor() internal {
-        _upgradeRelayHub(0x537F27a04470242ff6b2c3ad247A05248d0d27CE);
+        _upgradeRelayHub(0xD216153c06E857cD7f72665E0aF1d7D82172F494);
     }
 
     function _getRelayHub() internal view returns (address relayHub) {

test/gsn/GSNBouncerERC20Fee.test.js

@@ -41,7 +41,7 @@ contract('GSNBouncerERC20Fee', function ([_, sender, other]) {
   context('when relay-called', function () {
     beforeEach(async function () {
       await gsn.fundRecipient(web3, { recipient: this.recipient.address });
-      this.relayHub = await IRelayHub.at('0x537F27a04470242ff6b2c3ad247A05248d0d27CE');
+      this.relayHub = await IRelayHub.at('0xD216153c06E857cD7f72665E0aF1d7D82172F494');
     });
 
     it('charges the sender for GSN fees in tokens', async function () {

test/gsn/GSNContext.test.js

@@ -14,7 +14,7 @@ contract('GSNContext', function ([_, deployer, sender, newRelayHub]) {
   });
 
   describe('get/set RelayHub', function () {
-    const singletonRelayHub = '0x537F27a04470242ff6b2c3ad247A05248d0d27CE';
+    const singletonRelayHub = '0xD216153c06E857cD7f72665E0aF1d7D82172F494';
 
     it('initially returns the singleton instance address', async function () {
       expect(await this.context.getRelayHub()).to.equal(singletonRelayHub);

test/gsn/GSNRecipient.test.js

@@ -11,7 +11,7 @@ contract('GSNContext', function ([_, payee]) {
   });
 
   it('returns the RelayHub address address', async function () {
-    expect(await this.recipient.getHubAddr()).to.equal('0x537F27a04470242ff6b2c3ad247A05248d0d27CE');
+    expect(await this.recipient.getHubAddr()).to.equal('0xD216153c06E857cD7f72665E0aF1d7D82172F494');
   });
 
   it('returns the compatible RelayHub version', async function () {