git-p4: add failing test for "git-p4: respect excluded paths when detecting branches"

git-p4: add failing test for "git-p4: respect excluded paths when detecting branches"

In preparation for a fix, add a failing test case to test that
git-p4 doesn't exclude files despite being told to
when handling multiple branches.

I.e., it should exclude //depot/branch2/file2 when run with -//depot/branch2/file2,
but doesn't do this right now.

The test is based on 'git p4 clone complex branches' test with the following changes:
 * account for file3 moved from branch3 to branch4 in test 'git p4 submit to two branches in a single changelist';
 * account for branch6 created in test 'git p4 clone file subset branch';
 * file2 is expected to be missing from all branches due to explicit exclude.

Signed-off-by: Andrey Mazo <amazo@checkvideo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>