docs: fix link to GitLab.com
Created by: ghost
Correction of link to GitLab; Was pointing to GitHub.com > now points to GitLab.com; The section of relevant html is:
<a class="nav-edit-button btn btn-outline-secondary btn-sm" target="blank" href="https://github.com/sourcegraph/sourcegraph/edit/master/doc/integration/gitlab.md">Edit this page on GitHub</a>
</div>
<section class="column large-7 large-push-3 medium-6 medium-push-4 small-12 docs-content-section">
<div class="markdown-body"><h1 id="gitlab-integration-with-sourcegraph"><a name="gitlab-integration-with-sourcegraph" class="anchor" href="#gitlab-integration-with-sourcegraph" rel="nofollow" aria-hidden="true" title="#gitlab-integration-with-sourcegraph"></a>GitLab integration with Sourcegraph</h1>
<p>You can use Sourcegraph with <a href="https://gitlab.com">GitLab.com</a> and GitLab CE/EE.</p>
<table>
<thead>
<tr>
<th>Feature</th>
<th>Supported?</th>
</tr>
</thead>
Cheers!