poule: do not recognize "arm" as platform/arm

Some words such as "swarm" and "apparmor" were recognized as "arm".
So remove "arm" from the list at the moment.

Signed-off-by: Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
Upstream-commit: b7ca1568b157b7a67951207626a6605bcee4e282
Component: engine

components/engine/poule.yml

@@ -30,7 +30,7 @@
                 platform/desktop:    [ "docker for mac", "docker for windows" ],
                 platform/freebsd:    [ "freebsd" ],
                 platform/windows:    [ "nanoserver", "windowsservercore", "windows server" ],
-                platform/arm:        [ "raspberry", "arm", "raspbian", "rpi", "beaglebone", "pine64" ],
+                platform/arm:        [ "raspberry", "raspbian", "rpi", "beaglebone", "pine64" ],
             }
         }
       - type:       version-label