[submodule] Update submodule sonic-snmpagent to the latest HEAD autom…

…atically (#18023)

#### Why I did it
src/sonic-snmpagent
```
* 5d5cfe5 - (HEAD -> 202311, origin/202311) Set the execute bit on sysDescr_pass.py (#306) (3 days ago) [Andre Kostur]
```
#### How I did it
#### How to verify it
#### Description for the changelog