Fix immich-ml service: add venv bin to PATH so subprocess finds python

Co-authored-by: Joulinar <47155374+Joulinar@users.noreply.github.com>

Author: Copilot

dietpi/dietpi-software

@@ -12263,6 +12263,7 @@ SyslogIdentifier=Immich-ML
 User=immich
 WorkingDirectory=/opt/immich-ml
 Environment=NO_COLOR=true
+Environment=PATH=/opt/immich-ml/.venv/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
 EnvironmentFile=/mnt/dietpi_userdata/immich/immich-ml.env
 ExecStart=/opt/immich-ml/.venv/bin/python -m immich_ml