@Test
public void testWithContentTypeWithoutCharset() {

    // Arrange
    final DittoHeaders dittoHeaders = DittoHeaders.empty();
    final String type = MediaTypes.TEXT_PLAIN.toString();
    final ContentType typeMissingCharset = MediaTypes.TEXT_PLAIN.toContentTypeWithMissingCharset();
    // Act
    final TestRouteResult result =
            testRoute(extractRequestContext(
                    ctx -> ensureValidContentType(Set.of(type), ctx, dittoHeaders, COMPLETE_OK)))
                    .run(HttpRequest.PUT("someUrl").withEntity(typeMissingCharset, "something".getBytes()));
    // Assert
    result.assertStatusCode(StatusCodes.OK);
}