Fixes #2728 Change rhel service file to not use python

[Klaas-]

Description

Issue #2728

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[Klaas-]

Downstream patch: https://gitlab.com/redhat/centos-stream/rpms/WALinuxAgent/-/blob/c8s/wla-Use-platform-python-in-waagent.service.patch

[Klaas-]

https://bugzilla.redhat.com/show_bug.cgi?id=2170104#c38