chore: set yarn registry (#590)

Author: jjarvisp

.changeset/long-frogs-see.md

@@ -0,0 +1,2 @@
+---
+---

scripts/start_npm_proxy.ts

@@ -52,3 +52,6 @@ console.log(`Local npm proxy running at ${EXPECTED_URL}.`);
  */
 await execa('npm', ['config', 'set', 'registry', EXPECTED_URL]);
 console.log(`Set npm registry to ${EXPECTED_URL}`);
+
+await execa('yarn', ['config', 'set', 'registry', EXPECTED_URL]);
+console.log(`Set yarn registry to ${EXPECTED_URL}`);

scripts/stop_npm_proxy.ts

@@ -2,6 +2,7 @@ import { execa, execaCommand } from 'execa';
 
 const VERDACCIO_PORT = 4873;
 const NPM_REGISTRY = 'https://registry.npmjs.org/';
+const YARN_REGISTRY = 'https://registry.yarnpkg.com/';
 
 /**
  * Kills the process that is listening on VERDACCIO_PORT
@@ -13,6 +14,7 @@ const NPM_REGISTRY = 'https://registry.npmjs.org/';
  * https://github.com/sindresorhus/execa/blob/HEAD/docs/escaping.md
  */
 await execa('npm', ['config', 'set', 'registry', NPM_REGISTRY]);
+await execa('yarn', ['config', 'set', 'registry', YARN_REGISTRY]);
 
 // returns the process id of the process listening on the specified port
 let pid: number;