Make transpilation setup local to this repo (#4041)

Co-authored-by: Ernesto García <ernestognw@gmail.com>

hardhat.config.js

@@ -89,10 +89,11 @@ module.exports = {
     },
   },
   exposed: {
+    initializers: true,
     exclude: [
       'vendor/**/*',
-      // overflow clash
-      'utils/Timers.sol',
+      // Exclude Timers from hardhat-exposed because its overloaded functions are not transformed correctly
+      'utils/Timers{,Upgradeable}.sol',
     ],
   },
   docgen: require('./docs/config'),