Frontend assets with tilde in their names may trip firewalls

A user of a self-hosted GitLab instance had indicated they were receiving 404 responses for their javascript assets after upgrading to the latest version. It turns out this was due to the appearance of tilde ~ characters in webpack asset filenames following the upgrade to webpack v4.

Some firewall services like Barracuda Web Application Firewall block all requests that contain tilde in their urls due to an old IIS bug (documented here).

While this IIS vulnerability will not effect GitLab installations (since it is very unlikely somebody will try to host GitLab with a 6-year-old unpatched version of IIS), this firewall confusion may still effect them. I think it may be prudent to find a way to format the gitlab-ce~4107756 asset names in such a way that they do not contain tildes because recommending users modify the default settings of their firewall setup may make them uneasy.