Add timestamp based governor with EIP-6372 and EIP-5805 (#3934)

Co-authored-by: Francisco Giordano <fg@frang.io>
Co-authored-by: Ernesto García <ernestognw@gmail.com>
Co-authored-by: Francisco <frangio.1@gmail.com>

test/governance/utils/EIP6372.behavior.js

@@ -0,0 +1,23 @@
+const { clock } = require('../../helpers/time');
+
+function shouldBehaveLikeEIP6372(mode = 'blocknumber') {
+  describe('should implement EIP6372', function () {
+    beforeEach(async function () {
+      this.mock = this.mock ?? this.token ?? this.votes;
+    });
+
+    it('clock is correct', async function () {
+      expect(await this.mock.clock()).to.be.bignumber.equal(await clock[mode]().then(web3.utils.toBN));
+    });
+
+    it('CLOCK_MODE is correct', async function () {
+      const params = new URLSearchParams(await this.mock.CLOCK_MODE());
+      expect(params.get('mode')).to.be.equal(mode);
+      expect(params.get('from')).to.be.equal(mode == 'blocknumber' ? 'default' : null);
+    });
+  });
+}
+
+module.exports = {
+  shouldBehaveLikeEIP6372,
+};