[build] fix for ARM run-docker-example.sh script

When running the script on an Apple ARM CPU the script didn't correctly
figure out that it was running on ARM and started the x86_64 container
which runs very slow as this has to be run through the Rosetta emulator.

- fixes the pattern match, must use [[]] with == for regex expansion
- updated to latest ARMV8 image

containers/run-docker-example.sh

@@ -21,8 +21,8 @@ ARCH=X86-64
 DOCKER_IMAGE=daphneeu/daphne-dev
 DOCKER_TAG=latest_${ARCH}_BASE
 #DOCKER_TAG=latest_${ARCH}_CUDA
-if [ $(arch) == 'armv64'  ] || [ $(arch) == 'aarch64' ]; then
-    DOCKER_TAG=v0.2_ARMV8_BASE_ubuntu20.04
+if [[ "$(arch)" == arm*  ]] || [ $(arch) == 'aarch64' ]; then
+    DOCKER_TAG=latest_ARMV8_BASE
 fi
 
 #on some installations docker can only be run with sudo