[slave.mk]: remove updategraph.service generation in slave.mk (#3153)

Author: theasianpianist

slave.mk

@@ -644,8 +644,6 @@ $(addprefix $(TARGET_PATH)/, $(SONIC_INSTALLERS)) : $(TARGET_PATH)/% : \
 	j2 -f env files/initramfs-tools/union-mount.j2 onie-image.conf > files/initramfs-tools/union-mount
 	j2 -f env files/initramfs-tools/arista-convertfs.j2 onie-image.conf > files/initramfs-tools/arista-convertfs
 
-	j2 files/build_templates/updategraph.service.j2 > updategraph.service
-
 	$(if $($*_DOCKERS),
 		j2 files/build_templates/sonic_debian_extension.j2 > sonic_debian_extension.sh
 		chmod +x sonic_debian_extension.sh,