release: support kick off release in current branch

Currently when triggering release, it always pull remote repo and
checkout main branch. Any changes which are merged into the target
release branch (e.g. release-3.5) will be ignored. It isn't
convenient for test, including in github workflow and local environment.
So we need to support triggering release in current branch.

Note: --current-branch should only be called with DRY_RUN=true

Signed-off-by: Benjamin Wang <wachao@vmware.com>

scripts/build-binary.sh

@@ -7,7 +7,6 @@ source ./scripts/test_lib.sh
 VER=$1
 REPOSITORY="${REPOSITORY:-git@github.com:etcd-io/etcd.git}"
 
-
 if [ -z "$1" ]; then
   echo "Usage: ${0} VERSION" >> /dev/stderr
   exit 255
@@ -25,9 +24,7 @@ function setup_env {
 
   pushd "${proj}" >/dev/null
     run git fetch --all
-    git_assert_branch_in_sync || exit 2
     run git checkout "${ver}"
-    git_assert_branch_in_sync || exit 2
   popd >/dev/null
 }