update golangci-lint action to v3, golangci-lint to v1.48.0 (#3499)

* run gofmt -s -w

* stop using the deprecated io/ioutil package

* update golangci-lint action to v3, golangci-lint to v1.48.0

interop/http09/client.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"crypto/tls"
 	"errors"
-	"io/ioutil"
+	"io"
 	"log"
 	"net"
 	"net/http"
@@ -118,7 +118,7 @@ func (c *client) doRequest(req *http.Request) (*http.Response, error) {
 		ProtoMajor: 0,
 		ProtoMinor: 9,
 		Request:    req,
-		Body:       ioutil.NopCloser(str),
+		Body:       io.NopCloser(str),
 	}
 	return rsp, nil
 }

interop/http09/http_test.go

@@ -3,7 +3,7 @@ package http09
 import (
 	"crypto/tls"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net"
 	"net/http"
 	"net/http/httptest"
@@ -62,7 +62,7 @@ var _ = Describe("HTTP 0.9 integration tests", func() {
 		)
 		rsp, err := rt.RoundTrip(req)
 		Expect(err).ToNot(HaveOccurred())
-		data, err := ioutil.ReadAll(rsp.Body)
+		data, err := io.ReadAll(rsp.Body)
 		Expect(err).ToNot(HaveOccurred())
 		Expect(data).To(Equal([]byte("Hello World!")))
 	})
@@ -83,7 +83,7 @@ var _ = Describe("HTTP 0.9 integration tests", func() {
 		)
 		rsp, err := rt.RoundTrip(req)
 		Expect(err).ToNot(HaveOccurred())
-		data, err := ioutil.ReadAll(rsp.Body)
+		data, err := io.ReadAll(rsp.Body)
 		Expect(err).ToNot(HaveOccurred())
 		Expect(data).To(Equal([]byte("done")))
 	})

interop/http09/server.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 	"io"
-	"io/ioutil"
 	"log"
 	"net"
 	"net/http"
@@ -102,7 +101,7 @@ func (s *Server) handleConn(conn quic.Connection) {
 }
 
 func (s *Server) handleStream(str quic.Stream) error {
-	reqBytes, err := ioutil.ReadAll(str)
+	reqBytes, err := io.ReadAll(str)
 	if err != nil {
 		return err
 	}