Bump verible
To include the fix for
# See the License for the specific language governing permissions and
# limitations under the License.
-VERIBLE_VERSION=03c7102ab8ed63037159f479ce17b3487401f082
+VERIBLE_VERSION=751d4d8e57741ab22806f91982f59c71ecf37d9d
INSTALL_DIR=/tools/verible
# this requires the bazel build system and GCC7
