Merge branch 'main' into alechan/upgrade-xpk-v0.13.0

Author: aybchan

.github/container/Dockerfile.axlearn

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1-labs
 ARG BASE_IMAGE=ghcr.io/nvidia/jax-mealkit:jax
-ARG URLREF_AXLEARN=https://github.com/apple/axlearn.git
+ARG URLREF_AXLEARN=https://github.com/apple/axlearn.git#main
 ARG SRC_PATH_AXLEARN=/opt/axlearn
 ARG DEST_MANIFEST_DIR=/opt/manifest.d
 ARG GIT_USER_NAME=JAX Toolbox

.github/container/git-clone.sh

@@ -66,15 +66,17 @@ fi
 
 ## check out the source
 GIT_REPO=$(cut -d# -f1 <<< $GIT_URLREF)
-GIT_REF=$(cut -d# -f2- <<< $GIT_URLREF)
+GIT_REF=$(cut -s -d# -f2- <<< $GIT_URLREF)
 
 echo "Fetching $GIT_REPO#$GIT_REF to $DESTINATION"
 
 set -ex -o pipefail
 
 git clone ${GIT_REPO} ${DESTINATION}
 pushd ${DESTINATION}
-git checkout ${GIT_REF}
+if [[ -n "${GIT_REF}" ]]; then
+    git checkout ${GIT_REF}
+fi
 COMMIT_SHA=$(git rev-parse HEAD)
 git submodule update --init --recursive
 popd