Removed typehint to avoid failing testcases in php7

[wachterjohannes]

If scalar typehints are used prophecy generates wrong php code for mock classes. they will break the testcases (see https://travis-ci.org/sulu-io/sulu/jobs/102034955#L1028).

informations:

q	a
Fixed tickets	none
Related PRs	none
BC breaks	none
Documentation PR	none