[BUG] unnecessary linking to sshd

Description
- waagent.service has sshd in the Wants= section, which seems to serve no purpose, and can conflict with some edge-case configs where there is a 'different' sshd present.

Note: Please add some context which would help us understand the problem better
1. Section of the log where the error occurs.
n/a
2. Serial console output
n/a
3. Steps to reproduce the behavior.
disable sshd
restart waagent or the VM
watch sshd start up anyway due to the Wants= reference

**Distro and WALinuxAgent details (please complete the following information):**
- Situation that brought this to light was SUSE 15.7, but it could be any supported distro.
- WALinuxAgent version - Any. The service references in the unit filles are present in current code

**Additional context**
Creating this artificial link between sshd and waagent serves no purpose and definitely is not required for functionality. While the effect is exceedingly rare, it does happen and could be bringing in a package dependency on sshd.

**Log file attached**
n/a