Consolidate the output parsers in Compile and Application Output

With Creator 4.10, we now have the possibility to get QtTest failures from Compile Output to the Issues pane (QTCREATORBUG-8091).

This gives the following situation:

Compile Output:

• Compiler errors (on stderr, therefore printed in red) are clickable (but are no hyperlinks). These lines are transferred to the Issues pane
• Qt Test failures are not clickable and no hyperlinks, but are transferred to the Issues pane
• Custom failures using the "file:///path/to/file:line" syntax are not supported

Application Output

• Qt Test failures are hyperlinks and clickable, but they are not transferred to the Issues pane
• Custom failures using the "file:///path/to/file:line" are hyperlinks and clickable too, but also not transferred to Issues.

This leads to the following questions and suggestions:

1. Should the links in Compile Output be hyperlinks too?
2. Should Qt Test failures be clickable in Compile Output?
3. Can we support the "file://..." syntax in Compile Output?
4. Should errors from Application output be transferred to Issues pane also? I started https://codereview.qt-project.org/c/qt-creator/qt-creator/+/74090 long time ago for this, but never got it merged (but it can be re-animated)

Points 3 and 4 are especially interesting for "alien" test frameworks that are not supported by Qt Auto Test.