fix: use vanilla pino instance for logging (#465)

Author: gr2m

api/github/webhooks.js

@@ -1,8 +1,13 @@
 const { createNodeMiddleware, createProbot } = require("probot");
+const pino = require("pino");
 
 const app = require("../../app");
 
 module.exports = createNodeMiddleware(app, {
-  probot: createProbot(),
+  probot: createProbot({
+    overrides: {
+      log: pino(),
+    },
+  }),
   webhooksPath: "/api/github/webhooks",
 });