execsnoop fails to process app launched by kde 5.19's launcher

[huyz-git]

After kde 5.19 upgrade, apps launched by kde's launcher (e.g. plasmashell's launcher, krunner) will have separate cgroup like this:

And execsnoop no longer works for this type of apps.

However, for the same app launched by command line, execsnoop works without any problem.

[huyz-git]

For apps launched by kde's launcher, cgnoproxy --pid xxx works, start cgproxy.service after launch the app, (i.e. info: noproxy running process xxx) also works.
Only launch apps by kde's launcher when cgproxy.service is running, execsnoop doesn't work.

[springzfx]

KDE moved the process to their predefined scope(cgroup).
However it happened a bit late after cgproxy execsnoop, so the cgroup got override by kde.
https://invent.kde.org/libraries/kcgroups

[springzfx]

fix in bc94e58
For now the solution is to check again after small period(100ms) to avoid kde cgroup override.

Any suggestions are welcomed.