ethclient: add PeerCount method (#24849)

* adding peer count function

* Update ethclient.go
Co-authored-by: Felix Lange <fjl@twurst.com>

ethclient/ethclient.go

@@ -94,6 +94,13 @@ func (ec *Client) BlockNumber(ctx context.Context) (uint64, error) {
 	return uint64(result), err
 }
 
+// PeerCount returns the number of p2p peers as reported by the net_peerCount method.
+func (ec *Client) PeerCount(ctx context.Context) (uint64, error) {
+	var result hexutil.Uint64
+	err := ec.c.CallContext(ctx, &result, "net_peerCount")
+	return uint64(result), err
+}
+
 type rpcBlock struct {
 	Hash         common.Hash      `json:"hash"`
 	Transactions []rpcTransaction `json:"transactions"`