* MM-26425: Make URL parsing for image proxy more robust - We don't bypass protocol relative URLs. - We don't bypass hostnames with a similar prefix. https: //mattermost.atlassian.net/browse/MM-26425 ```release-note NONE ``` * fix tests and incorporate review comments * Handle opaque URLs * Fix path tests Co-authored-by: Mattermod <mattermod@users.noreply.github.com>