TUN-4961: Update quic-go to latest

- Updates fips-go to be the latest on cfsetup.yaml
- Updates sumtype's x/tools to be latest to avoid Internal: nil pkg
  errors with fips.

vendor/github.com/lucas-clemente/quic-go/quicvarint/io.go

@@ -0,0 +1,65 @@
+package quicvarint
+
+import (
+	"bytes"
+	"io"
+)
+
+// Reader implements both the io.ByteReader and io.Reader interfaces.
+type Reader interface {
+	io.ByteReader
+	io.Reader
+}
+
+var _ Reader = &bytes.Reader{}
+
+type byteReader struct {
+	io.Reader
+}
+
+var _ Reader = &byteReader{}
+
+// NewReader returns a Reader for r.
+// If r already implements both io.ByteReader and io.Reader, NewReader returns r.
+// Otherwise, r is wrapped to add the missing interfaces.
+func NewReader(r io.Reader) Reader {
+	if r, ok := r.(Reader); ok {
+		return r
+	}
+	return &byteReader{r}
+}
+
+func (r *byteReader) ReadByte() (byte, error) {
+	var b [1]byte
+	_, err := r.Reader.Read(b[:])
+	return b[0], err
+}
+
+// Writer implements both the io.ByteWriter and io.Writer interfaces.
+type Writer interface {
+	io.ByteWriter
+	io.Writer
+}
+
+var _ Writer = &bytes.Buffer{}
+
+type byteWriter struct {
+	io.Writer
+}
+
+var _ Writer = &byteWriter{}
+
+// NewWriter returns a Writer for w.
+// If r already implements both io.ByteWriter and io.Writer, NewWriter returns w.
+// Otherwise, w is wrapped to add the missing interfaces.
+func NewWriter(w io.Writer) Writer {
+	if w, ok := w.(Writer); ok {
+		return w
+	}
+	return &byteWriter{w}
+}
+
+func (w *byteWriter) WriteByte(c byte) error {
+	_, err := w.Writer.Write([]byte{c})
+	return err
+}