In the process of taking advantage of 'convert_mapping_to_xml()',
commit:7ebe78979166e36a038a116788c33383878ced20 renamed 'block-level' to
'blocking-level' in the build-blocker property.
Another unrelated commit modified the test to use 'block_level' instead
of 'block-level'.
Change-Id: I2dd642ec4966c4c48e0a35e986a69b3b74803358
Signed-off-by: Trevor Bramwell <tbramwell@linuxfoundation.org>