Remove `libnativeloader_test` from `libnativeloader/TEST_MAPPING`.

This test is already part of ART's top-level `TEST_MAPPING` file
(since https://android-review.googlesource.com/1999712), so it is
already run as part of presubmit tests triggered by a change in a file
under directory `libnativeloader`, as TreeHugger runs presubmit tests
of that's file's directory as well as its parent directories (see
go/test-mapping#treehugger-presubmit-with-test_mapping).

Test: atest --test-mapping art/libnativebridge:presubmit
Test: art/libnativebridge/tests/runtests.sh
Bug: 143943613
Bug: 152374989
Change-Id: Ia222c9c49e68f9c8a351ee69ae8c801624cc5e5a
1 file changed