Updated version of webpack-dev-server due to security vulnerability.

Commits

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<tr><td colspan=3><h3>@angular/cli (6.2.9)</h3></td></tr> <tr> <td><b>Commit</b> <td><b>Description</b> <td><b>Notes</b> </tr>

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<td> <a href="https://github.com/angular/angular-cli/commit/2fa37c639808c87d092b57bbb2fee3ce91ef78bd"><img align="top" title="Feature" src="https://img.shields.io/badge/2fa37c6-fix-green.svg" /> </a> </td>

<td>'ng add' selects supported version via peer dependencies</td>

<td>

<a href="https://github.com/angular/angular-cli/issues/12914"> [Closes #12914]<br /> </a>

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</tbody> </table>