Running integration tests should not result in testfiles appearing in recent files

[h-man2]

Is your feature request related to a problem? Please describe.
When integration tests are executet, the opened files appear in the recent files list.
This kicks out userspecific files which is annoying.

Describe the solution you'd like
Running integration tests should not change the recent files list.
This can be done by evaluating the program argument -t that specifes the testmode (Options.testMode) of USE.

Additional context
Integration tests are run like unit tests. See org.tzi.use.main.ShellIT.