block markup for these core blocks has been updated in core since block-unit-test was last released. than whats already in block-unit-test; so add these blocks
add a new block of when image block is centered aligned, with caption (without caption, block markup is same);
image block is left aligned; without caption (a left aligned image block with a caption didnt exist previously in this)
image block is right aligned; with caption (a right aligned image block with no caption didnt exist previously in this)