feat(ci): set daemon version from git metadata

Author: git-developer

Dockerfile

@@ -29,26 +29,19 @@ RUN <<EOR
   set -eu
 
   ##
-  # Converts the output of `git describe` to a valid python version (PEP 440)
-  #
-  # Examples:
-  # - v0.4.9.2                 -> 0.4.9.2
-  # - ver0.4.8.11-3-123-g030686f -> 0.4.8.11.3.123.dev3172463
-  #
-  # References:
-  # - https://packaging.python.org/en/latest/specifications/version-specifiers/#version-specifiers
+  # Converts the output of `git describe` to a valid python version (PEP 440),
+  # e.g. `v0.4.9.2` to `0.4.9.2` or `ver0.4.8.11-3-123-g030686f` to `0.4.8.11.3.123.dev3172463`
   ##
   convert_git_description_to_python_version() {
     description="${1}"
-
+    hash="${description##*-g}"
     version="$(printf %s "${description%-g*}" | tr -c -s [0-9.] .)"
     version="${version#.}"
     version="${version%.}"
-    hash="${description##*-g}"
     if [ "${hash}" != "${description}" ]; then
       version="${version}.dev$(printf %d "0x${hash}")"
     fi
-    echo "${version}"
+    printf '%s\n' "${version}"
   }
   if [ -z "${DAEMON_VERSION-}" ] && [ "${GIT_DESCRIPTION-}" ]; then
     DAEMON_VERSION="$(convert_git_description_to_python_version "${GIT_DESCRIPTION}")"