Hang on jsdoc comment with default value

[mjbvz]

TS and JS Grammar Extension version: 0.0.22 / latest

From microsoft/vscode#34164

Code

/**
 * @param {boolean} [settings.debug= - Print getUpdate results in console.
 */

Bug
Grammar hangs while parsing

[sheetalkamat]

Note as discussed in the PR, we get our jsdoc grammar from https://github.com/atom/language-javascript