Set with key type nftables.TypeIFName not working

Creating a set with Type: nftables.TypeIFName seems to work, but the set acts strangely.

*Sample code for set:*
```go
conn.AddSet(&nftables.Set{
Table: table,
Name: "test_set",
KeyType: nftables.TypeIFName,
}, nil)
```

I also created a set called "manual_set" manually, and they both list:

*nftables pkg set and nft cli set*
```sh
% nft 'add set test_table manual_set { type ifname; }'
% nft list table test_table
table ip test_table {
set test_set {
type ifname
}

set manual_set {
type ifname
}
}
```

I then added an element into each set using nft cli and they both seem to succeed, however ***the set created by this package shows empty elements***.

*Added Elements*
```sh
% nft 'add element test_table test_set { "wg0" }'
% nft 'add element test_table manual_set { "wg0" }'
% nft list table test_table   ☸ kubernetes-admin@50w_k8s:argocd 
table ip test_table {
set test_set {
type ifname
elements = { "" }
}

set manual_set {
type ifname
elements = { "wg0" }
}
}
```

Additionally, trying to add an element through this package fails for either table, though I do wonder if I've missed something in my code:

*Attempt to add set element to both tables*
```go
// github.com/google/nftables set and manual set
testSet, _ := c.GetSetByName(table, "test_set")
manualSet, _ := c.GetSetByName(table, "manual_set")

// Second Element
elements := []nftables.SetElement{{Key: []byte("wg1")}}

c.SetAddElements(manualSet, elements)
c.SetAddElements(testSet, elements)

if err := c.Flush(); err != nil {
log.Panicf("Error: %s", err)
}
```

Running returns error: "conn.Receive: netlink receive: invalid argument"

I've tried a few different key types and have only had success with TypeFamilyIPv4.