Wrong chrony stratum (doc has updated, AgentBaker has not)

**What happened**:
A lot of files have
```
refclock PHC /dev/ptp0 poll 3 dpoll -2 offset 0
```

**What you expected to happen**:
```
refclock PHC /dev/ptp_hyperv poll 3 dpoll -2 offset 0 stratum 2
```
like in current version of https://learn.microsoft.com/en-us/azure/virtual-machines/linux/time-sync should be instead present. Or if you don't want ptp_hyperv, ptp0 is okay; what matters is `stratum 2`

**How to reproduce it**:
Use grep on the existing source files.

**Anything else we need to know?**:
Wrong stratum leads to user confusion in https://www.mail-archive.com/chrony-users@chrony.tuxfamily.org/msg03770.html.

**Environment**:

- AgentBaker version: HEAD
- Kubernetes version (use `kubectl version`):
- OS (e.g. from /etc/os-release):
- Kernel (e.g. `uname -a`):
- Install tools:
- Others:

Use grep across the existing source files for `refclock PHC` and compare the current entries with the Azure time-sync documentation linked in the issue. Update the relevant chrony configuration so the entry includes `stratum 2`, then verify that the affected source files no longer contain the incorrect stratum.

Written by the indexing model from the issue text.