test(example-event-handlers): link tracking issue from hardfork workaround

Link #2127 from the cancun-hardfork comment so anyone touching the
file finds the tracking ticket for the proper fix (deterministic
hardhat version via lockfile or pinned version).

Author: lutter

examples/ethereum-basic-event-handlers/hardhat/hardhat.config.js

@@ -4,6 +4,7 @@ module.exports = {
     hardhat: {
       // Pin to Cancun: Prague (default in hardhat >=2.26) enforces EIP-7825's
       // per-transaction gas cap of 2^24, which rejects the test deployments.
+      // Tracking proper fix (pin hardhat / lockfile / fit gas cap) in #2127.
       hardfork: 'cancun',
     },
   },