Move the two separate RUN commands into one statement. (#74)
Move the two separate RUN commands into one statement. (#74)

This avoids a bug (only on aarch64) where a certain combinations
of RUN and ADD commands causes Docker to fail to build the
image.

Signed-off-by: Chris Lalancette <281cd07d7578d97c83271fbbf2faddb83ab3791c@osrfoundation.org>
ros2/ci,ros2/ci,ros2/ci