client: docker-finance.d: hledger: add docker-finance version tag

client/docker-finance.d/container/hledger/hledger.conf.in

@@ -15,6 +15,8 @@
 # You should have received a copy of the GNU General Public License
 # along with this program. If not, see <https://www.gnu.org/licenses/>.
 
+# docker-finance @DOCKER_FINANCE_VERSION@
+
 # NOTE:
 #  - File is treated as a plain configuration file (non-executable)
 #  - See sample: https://github.com/simonmichael/hledger/blob/master/hledger.conf.sample