Fixed bugs with link preview

[Zabuzard]

Overview

This fixes a couple of bugs with link previews.

Major priority, because the feature is currently live and many tags dont work anymore due to it.

Fixed bugs

1. Sometimes included trailing punctation, like http://www.example.com/, or http://www.example.com/.
2. Did not respect escaped URLs, like <http://www.example.com/>
3. The link detector has a lot of false positives, such as System.in being detected as http://System.in/. Now filters out everything that is not http on the original URL.
4. Some websites use <meta name="..."> instead of <meta property="...">
5. When an individual query failed with an exception, it crashed the whole query instead of being skipped. Solved by using .exceptionally(...) with a proper log.warn on each task individually.
6. When the full query failed with an exception, it lead to not sending the actual /tag anymore (stuck forever). Solved by using .exceptionally(...) with a proper log.error on the surrounding all-task
7. Forgot a proper timeout for bad websites. Now is 10 seconds per website.

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

0.0% Coverage
0.0% Duplication

[Zabuzard]

gonna ship this today. merging with one approval