Currently, there is support for setting up a SecurityContext after @Before by
using TestExecutionEvent.TEST_EXECUTION. The current implementation, however,
already creates the SecurityContext in @Before and just does not set it yet.
This leads to issues like #6591. For the case of @WithUserDetails, the
creation of the SecurityContext already looks up a user from the repository.
If the user was inserted in @Before, the user is not found despite using
TestExecutionEvent.TEST_EXECUTION. This commit changes the creation of the
SecurityContext to happen after @Before if using
TestExecutionEvent.TEST_EXECUTION.
Closes gh-6591
97ee6d66f1