chore(Makefile) upgrading go-dev container to v1.28.3

Signed-off-by: Cryptophobia <[email protected]>

Makefile

@@ -2,15 +2,15 @@ SHORT_NAME := slugrunner
 
 export GO15VENDOREXPERIMENT=1
 
-IMAGE_PREFIX ?= deis
+IMAGE_PREFIX ?= hephy
 
 include versioning.mk
 
 SHELL_SCRIPTS = $(wildcard rootfs/bin/*) $(wildcard rootfs/runner/*) $(wildcard _scripts/*.sh)
 
 # The following variables describe the containerized development environment
 # and other build options
-DEV_ENV_IMAGE := quay.io/deis/go-dev:0.20.0
+DEV_ENV_IMAGE := hephy/go-dev:v1.28.3
 DEV_ENV_WORK_DIR := /go/src/${REPO_PATH}
 DEV_ENV_CMD := docker run --rm -v ${CURDIR}:${DEV_ENV_WORK_DIR} -w ${DEV_ENV_WORK_DIR} ${DEV_ENV_IMAGE}
 DEV_ENV_CMD_INT := docker run -it --rm -v ${CURDIR}:${DEV_ENV_WORK_DIR} -w ${DEV_ENV_WORK_DIR} ${DEV_ENV_IMAGE}