Blacklist ament_black from RHEL-9 (#297)

It requires two packages that don't seem to have packages in RHEL: python3-uvloop and black.  Just disable the package.

Signed-off-by: Chris Lalancette <[email protected]>

rolling/release-rhel-build.yaml

@@ -14,6 +14,7 @@ notifications:
   maintainers: false
 package_blacklist:
 - acado_vendor  # Requires unreleased changes
+- ament_black  # python3-uvloop and black have no RPM packages for RHEL
 - ament_download  # Build failures on RHEL https://github.com/samsung-ros/ament_download/pull/3
 - control_box_rst  # coinor-libipopt-dev has no RPM for RHEL 9
 - four_wheel_steering_msgs  # Requires unreleased changes