[submodule] Update submodule sonic-platform-common to the latest HEAD automatically (#18008)

#### Why I did it
src/sonic-platform-common
```
* 7c2ad66 - (HEAD -> 202311, origin/202311) Tx/Rx power values should be rounded up to 3 decimal places (#432) (4 hours ago) [mihirpat1]
```
#### How I did it
#### How to verify it
#### Description for the changelog

Author: mssonicbld