[submodule] Update submodule sonic-swss to the latest HEAD automatica…

…lly (#19707)

#### Why I did it
src/sonic-swss
```
* 51a5b51f - (HEAD -> 202405, origin/202405) Add a check if OID exists before setting Host Tx Ready Signal Enable (#3232) (7 hours ago) [noaOrMlnx]
```
#### How I did it
#### How to verify it
#### Description for the changelog