Update to ldj 0.7.3
Update to ldj 0.7.3

No other changes planned in the short term, so let's jump on the latest
version.

Signed-off-by: Alexandre Montplaisir <0b9d8e7da097b5bbfe36e48cca5acfe475f18227@efficios.com>

efficios/jabberwocky,efficios/jabberwocky