docs: fix duplicate reference name
docs: fix duplicate reference name

this led to a warning during doc building

bobvanderlinden/machinekit,jaguarcat79/ILC-with-LinuxCNC,EqAfrica/machinekit,Cid427/machinekit,narogon/linuxcnc,kinsamanka/machinekit,araisrobo/machinekit,strahlex/machinekit,ianmcmahon/linuxcnc-mirror,RunningLight/machinekit,cnc-club/linuxcnc,RunningLight/machinekit,ikcalB/linuxcnc-mirror,RunningLight/machinekit,kinsamanka/machinekit,jaguarcat79/ILC-with-LinuxCNC,araisrobo/linuxcnc,kinsamanka/machinekit,cdsteinkuehler/MachineKit,kinsamanka/machinekit,unseenlaser/machinekit,bmwiedemann/linuxcnc-mirror,araisrobo/machinekit,strahlex/machinekit,araisrobo/linuxcnc,ArcEye/MK-Qt5,Cid427/machinekit,araisrobo/machinekit,unseenlaser/machinekit,ArcEye/machinekit-testing,EqAfrica/machinekit,mhaberler/machinekit,ianmcmahon/linuxcnc-mirror,ArcEye/machinekit-testing,araisrobo/machinekit,araisrobo/machinekit,EqAfrica/machinekit,mhaberler/machinekit,bobvanderlinden/machinekit,araisrobo/machinekit,cnc-club/linuxcnc,unseenlaser/linuxcnc,mhaberler/machinekit,strahlex/machinekit,cnc-club/linuxcnc,ikcalB/linuxcnc-mirror,kinsamanka/machinekit,ArcEye/machinekit-testing,RunningLight/machinekit,Cid427/machinekit,ikcalB/linuxcnc-mirror,EqAfrica/machinekit,bmwiedemann/linuxcnc-mirror,RunningLight/machinekit,ikcalB/linuxcnc-mirror,ArcEye/MK-Qt5,araisrobo/machinekit,cdsteinkuehler/MachineKit,ArcEye/machinekit-testing,ikcalB/linuxcnc-mirror,aschiffler/linuxcnc,Cid427/machinekit,unseenlaser/machinekit,cdsteinkuehler/linuxcnc,bmwiedemann/linuxcnc-mirror,ArcEye/MK-Qt5,ianmcmahon/linuxcnc-mirror,bmwiedemann/linuxcnc-mirror,mhaberler/machinekit,strahlex/machinekit,Cid427/machinekit,unseenlaser/machinekit,unseenlaser/linuxcnc,kinsamanka/machinekit,bobvanderlinden/machinekit,cnc-club/linuxcnc,bobvanderlinden/machinekit,mhaberler/machinekit,EqAfrica/machinekit,ianmcmahon/linuxcnc-mirror,ianmcmahon/linuxcnc-mirror,araisrobo/linuxcnc,ArcEye/MK-Qt5,jaguarcat79/ILC-with-LinuxCNC,ArcEye/MK-Qt5,ArcEye/machinekit-testing,araisrobo/machinekit,aschiffler/linuxcnc,ArcEye/MK-Qt5,narogon/linuxcnc,narogon/linuxcnc,cnc-club/linuxcnc,ArcEye/MK-Qt5,cnc-club/linuxcnc,cdsteinkuehler/linuxcnc,mhaberler/machinekit,cdsteinkuehler/MachineKit,cdsteinkuehler/linuxcnc,EqAfrica/machinekit,RunningLight/machinekit,Cid427/machinekit,unseenlaser/linuxcnc,araisrobo/machinekit,araisrobo/linuxcnc,cdsteinkuehler/linuxcnc,narogon/linuxcnc,ikcalB/linuxcnc-mirror,cdsteinkuehler/linuxcnc,EqAfrica/machinekit,cdsteinkuehler/MachineKit,unseenlaser/machinekit,kinsamanka/machinekit,mhaberler/machinekit,ArcEye/machinekit-testing,araisrobo/linuxcnc,bmwiedemann/linuxcnc-mirror,strahlex/machinekit,jaguarcat79/ILC-with-LinuxCNC,Cid427/machinekit,ikcalB/linuxcnc-mirror,strahlex/machinekit,EqAfrica/machinekit,bmwiedemann/linuxcnc-mirror,aschiffler/linuxcnc,bmwiedemann/linuxcnc-mirror,bobvanderlinden/machinekit,unseenlaser/linuxcnc,ianmcmahon/linuxcnc-mirror,unseenlaser/machinekit,RunningLight/machinekit,kinsamanka/machinekit,aschiffler/linuxcnc,ArcEye/machinekit-testing,unseenlaser/machinekit,unseenlaser/linuxcnc,unseenlaser/machinekit,bobvanderlinden/machinekit,bobvanderlinden/machinekit,Cid427/machinekit,cnc-club/linuxcnc,RunningLight/machinekit,cdsteinkuehler/MachineKit,ianmcmahon/linuxcnc-mirror,ArcEye/MK-Qt5,ArcEye/machinekit-testing,cdsteinkuehler/linuxcnc,bobvanderlinden/machinekit,aschiffler/linuxcnc,cdsteinkuehler/MachineKit,jaguarcat79/ILC-with-LinuxCNC,mhaberler/machinekit,narogon/linuxcnc,strahlex/machinekit