Simplify create_workspace.sh: remove unnecessary checkout

create_workspace.sh used to check out develop by default. However, this
is unnecessary because the script later checks out a specific reference
(which can be a commit ID, which is not accepted by git clone, the
reason we don't check out during clone); the repository will simply be
empty in the beginning, which should not be a problem.

Further, it is problematic because we use this script for the build of
the L2sim proxy, and the repository does not have develop; thus, without
this modification, L2sim proxy build will always fail.

ci-scripts/scripts/create_workspace.sh

@@ -15,7 +15,7 @@ ref=$3
 merge=$4
 
 rm -rf ${dir}
-git clone --filter=blob:none -n -b develop ${repo} ${dir}
+git clone --filter=blob:none -n ${repo} ${dir}
 cd ${dir}
 git config user.email "jenkins@openairinterface.org"
 git config user.name "OAI Jenkins"