Do not check mocha exit code on watch

test/integration/options/watch.spec.js

@@ -144,16 +144,11 @@ describe('--watch', function() {
  *
  * Returns child process and a promise for the test results. The test results
  * are an array of JSON objects generated by the JSON reporter.
- *
- * Checks that the exit code of the mocha command is 130, i.e. mocha was killed
- * by SIGINT.
  */
 function runMochaJSONWatchAsync(args, spawnOpts) {
   args = [...args, '--watch'];
   const [mocha, mochaDone] = runMochaJSONRawAsync(args, spawnOpts);
   const testResults = mochaDone.then(data => {
-    expect(data.code, 'to be', sigintExitCode);
-
     const testResults = data.output
       // eslint-disable-next-line no-control-regex
       .replace(/\u001b\[\?25./g, '')