add libpq-devel to Dockerfile.functional so that psycopg2 can be compiled on ARM (#1359)
add libpq-devel to Dockerfile.functional so that psycopg2 can be compiled on ARM (#1359)

Signed-off-by: Vijay Pillai <18f312bdf60e904fafd21533f511feb02ea2c0b3@anchore.com>
anchore/anchore-engine,anchore/anchore-engine,anchore/anchore-engine