meta-python: remove obsolete dependencies on python3-six

These recipes no longer use six, so remove the dependency.

The list of recipes that still use six is a somewhat useful proxy for
packages that are no longer maintained...

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>

meta-python/recipes-devtools/python/python3-cassandra-driver_3.29.3.bb

@@ -22,7 +22,6 @@ RDEPENDS:${PN} += "\
     python3-misc \
     python3-multiprocessing \
     python3-numbers \
-    python3-six \
     libevent \
 "