s3:tests: add a lot more tests to test_symlink_traversal_smb2.sh

s3:tests: add a lot more tests to test_symlink_traversal_smb2.sh

We now also test more path components checking the difference between
OBJECT_NAME_NOT_FOUND and OBJECT_PATH_NOT_FOUND.

We also test with symlinks within the path instead of only checking
symlinks as final path components (at least for the dirfsp part).

This ensures the following commits won't introduce regressions
when adding the openat2(RESOLVE_NO_SYMLINK) optimization.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>
BUG: https://bugzilla.samba.org/show_bug.cgi?id=15146
(cherry picked from commit 085f14857531dab179af66a69962486c7dd2592c)