Fix build break with 1.65.1 boost version

Fix build break with 1.65.1 boost version

This is a quick syntax fix. In other places of security-manager tests
a colon is used after BOOST_GLOBAL_FIXTURE macro usage, see:
tests/security-manager-tests.cpp:53:BOOST_GLOBAL_FIXTURE(TestConfig);
tests/security-manager-tests.cpp:54:BOOST_GLOBAL_FIXTURE(LogSetup);

The macro should be replaced anyway as it is deprecated according
to the boost documentation:
	https://www.boost.org/doc/libs/1_65_1/libs/test/doc/html/boost_test/utf_reference/test_org_reference/test_org_boost_global_fixture.html

Change-Id: Ib0ee486ae617b83b6f2e66a1b9b0d158b7cbfbec
Signed-off-by: Lukasz Wojciechowski <l.wojciechow@partner.samsung.com>