When resolving a user's roles, if there are any roles that depend on DLS/FLS, and that is not permitted by the current license, we skip them.
https://github.com/elastic/elasticsearch/blob/f435488484ec844962d49371b8917c135fe6f714/x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authz/store/CompositeRolesStore.java#L188-L192

However, we do not perform any logging in this circumstance, and rely on the user discovering that their roles are missing.

We should
1. Add a `WARN` log message
2. Add a Warning header

when this occurs. 
x-pack/plugin/security/src/test/java/org/elasticsearch/xpack/security/authz/store/CompositeRolesStoreTests.java
doCallRealMethod().when(fileRolesStore).accept(anySet(), anyActionListener());
        final NativeRolesStore nativeRolesStore = mock(NativeRolesStore.class);
        doCallRealMethod().when(nativeRolesStore).accept(anySet(), anyActionListener());
        when(fileRolesStore.roleDescriptors(anySet())).thenReturn(Collections.emptySet());
        doAnswer((invocationOnMock) -> {
            @SuppressWarnings("unchecked")
            ActionListener<RoleRetrievalResult> callback = (ActionListener<RoleRetrievalResult>) invocationOnMock.getArguments()[1];
            callback.onResponse(RoleRetrievalResult.success(Collections.emptySet()));
            return null;
        }).when(nativeRolesStore).getRoleDescriptors(isASet(), anyActionListener());
        final ReservedRolesStore reservedRolesStore = spy(new ReservedRolesStore());
        final Settings settings = Settings.builder()
            .put(SECURITY_ENABLED_SETTINGS)
            .put("xpack.security.authz.store.roles.negative_lookup_cache.max_size", 0)
            .build();
        final AtomicReference<Collection<RoleDescriptor>> effectiveRoleDescriptors = new AtomicReference<Collection<RoleDescriptor>>();
        final CompositeRolesStore compositeRolesStore = buildCompositeRolesStore(
            settings,
            fileRolesStore,
            nativeRolesStore,
            reservedRolesStore,
            null,
            null,
            null,
            null,
            null,
            rds -> effectiveRoleDescriptors.set(rds)
        );
        verify(fileRolesStore).addListener(anyConsumer()); 
        final String roleName = randomAlphaOfLengthBetween(1, 10);