jibri: don't provide a non-existing finalizer path

jibri/rootfs/defaults/config.json

@@ -1,7 +1,9 @@
 {
     "recording_directory":"{{ .Env.JIBRI_RECORDING_DIR }}",
     // The path to the script which will be run on completed recordings
+{{ if .Env.JIBRI_FINALIZE_RECORDING_SCRIPT_PATH -}}
     "finalize_recording_script_path": "{{ .Env.JIBRI_FINALIZE_RECORDING_SCRIPT_PATH }}",
+{{ end -}}
     "xmpp_environments": [
         {
             // A friendly name for this environment which can be used

jibri/rootfs/etc/cont-init.d/10-config

@@ -39,6 +39,7 @@ usermod -aG ${host_audio_group} jibri
 
 # script for finalizing must have executing bit.
 [ ! -z "${JIBRI_FINALIZE_RECORDING_SCRIPT_PATH}" ] \
+&& [ -f "${JIBRI_FINALIZE_RECORDING_SCRIPT_PATH}" ] \
 && [ ! -x "${JIBRI_FINALIZE_RECORDING_SCRIPT_PATH}" ] \
 && chmod +x ${JIBRI_FINALIZE_RECORDING_SCRIPT_PATH}