fix: ensure label-nodes systemd service can be enabled

[jackfrancis]

Reason for Change:

This PR fixes missing configuration data in the label-nodes systemd service so that it can be enabled for automatic start upon reboot.

Issue Fixed:

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Notes:

[mboersma]

/lgtm

[acs-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jackfrancis, mboersma

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[codecov]

Codecov Report

Merging #2915 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #2915   +/-   ##
======================================
  Coverage    72.5%   72.5%           
======================================
  Files         141     141           
  Lines       25757   25757           
======================================
  Hits        18676   18676           
  Misses       5999    5999           
  Partials     1082    1082