docs: replace outdated package paths described in rpc README (#10505)

Closes #10498

client/rpc/README.md

@@ -2,7 +2,7 @@
 
 > IPFS CoreAPI implementation using HTTP API
 
-This packages implements [`coreiface.CoreAPI`](https://pkg.go.dev/github.com/ipfs/boxo/coreiface#CoreAPI) over the HTTP API.
+This package implements [`coreiface.CoreAPI`](https://pkg.go.dev/github.com/ipfs/kubo/core/coreiface#CoreAPI) over the HTTP API.
 
 ## Documentation
 
@@ -16,29 +16,33 @@ Pin file on your local IPFS node based on its CID:
 package main
 
 import (
-    "context"
-    "fmt"
+	"context"
+	"fmt"
 
-    "github.com/ipfs/kubo/client/rpc"
-    path "github.com/ipfs/boxo/coreiface/path"
+	"github.com/ipfs/boxo/path"
+	"github.com/ipfs/go-cid"
+	"github.com/ipfs/kubo/client/rpc"
 )
 
 func main() {
-    // "Connect" to local node
-    node, err := rpc.NewLocalApi()
-    if err != nil {
-        fmt.Printf(err)
-        return
-    }
-    // Pin a given file by its CID
-    ctx := context.Background()
-    cid := "bafkreidtuosuw37f5xmn65b3ksdiikajy7pwjjslzj2lxxz2vc4wdy3zku"
-    p := path.New(cid)
-    err = node.Pin().Add(ctx, p)
-    if err != nil {
-    	fmt.Printf(err)
-        return
-    }
-    return
+	// "Connect" to local node
+	node, err := rpc.NewLocalApi()
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	// Pin a given file by its CID
+	ctx := context.Background()
+	c, err := cid.Decode("bafkreidtuosuw37f5xmn65b3ksdiikajy7pwjjslzj2lxxz2vc4wdy3zku")
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	p := path.FromCid(c)
+	err = node.Pin().Add(ctx, p)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
 }
 ```