[202012] [sonic-swss] update submodule pointer (#10456)

```
323dc34 [neighsyncd] increase neighsyncd timeout (#2209)
7f99941 Remove redundant and problematic code to skip "pool" field in buffer profile handling (#2197)
f3a0feb [Vxlanmgr] vnet netdev cleanup during config reload fix (#2191)
13ccaba Fix issue: sometimes PFC WD unable to create zero buffer pool (#2185)
```

Signed-off-by: Stepan Blyschak <stepanb@nvidia.com>