The plugin should use normal vscode variable expansion

[nolange]

I tried the VScode plugin with this setting:

  "codechecker.backend.outputFolder": "/tmp/${workspaceFolderBasename}/_build/.codechecker"

Turns out there is no "normal" variable expansion, like described here.

In combination with other plugins, full support could re-use existing vairbales (like ${command:cmake.buildDirectory})