fix: remove default got user-agent

Author: panva

lib/helpers/request.js

@@ -13,8 +13,12 @@ const cacheable = new CacheableLookup({
 });
 
 module.exports = async function request(options) {
+  Object.assign(options, {
+    url: new URL(options.url),
+    headers: options.headers || {},
+  });
   // eslint-disable-next-line no-param-reassign
-  options.url = new URL(options.url);
+  options.headers['user-agent'] = undefined;
   const { timeout, agent, lookup } = instance(this).configuration('httpOptions')(new URL(options.url));
   const helperOptions = omitBy({ timeout, agent, lookup }, Boolean);