```
It is assumed that ideally only one BasicTestingSetup exists at any
point in time for each process (due to use of globals).
This assumption is violated in the GUI tests, as a testing setup is
created as the first step of the main function and then (sometimes)
another one for the following test cases.
So, the gui tests create two testing setups:
BasicTestingSetup in main (added in fa4a04a)
a testing setup for individual test cases
Avoid that by destructing the testing setup in main after creation and
then move the explicit ECC_Stop to the only places where it is needed
(before and after apptests).
```
Backport of core PR16294.
Depends on D5556.