add fetch

.ci/github/files_between_commits.sh

@@ -1,8 +1,10 @@
 #!/bin/sh
 
-branch=${1#refs/}
+branch=$1
 hash=$2
 
+git fetch origin
+
 # root folder of added files
 git diff --color --name-only --diff-filter=A ${branch}..${hash} | cut -d/ -f1 || exit 1