all: update go.mod x/net dependency

Not necessary for anything, but need to test something harmless.

Change-Id: I4faa64ef2c8f1f14df5ccaa37836fc56beed4f50
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/566917
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
diff --git a/go.mod b/go.mod
index 9cde59c..5954e5d 100644
--- a/go.mod
+++ b/go.mod
@@ -3,7 +3,7 @@
 go 1.18
 
 require (
-	golang.org/x/net v0.10.0 // tagx:ignore
+	golang.org/x/net v0.21.0 // tagx:ignore
 	golang.org/x/sys v0.17.0
 	golang.org/x/term v0.17.0
 )
diff --git a/go.sum b/go.sum
index 55835d5..70b680b 100644
--- a/go.sum
+++ b/go.sum
@@ -1,5 +1,5 @@
-golang.org/x/net v0.10.0 h1:X2//UzNDwYmtCLn7To6G58Wr6f5ahEAQgKNzv9Y951M=
-golang.org/x/net v0.10.0/go.mod h1:0qNGK6F8kojg2nk9dLZ2mShWaEBan6FAoqfSigmmuDg=
+golang.org/x/net v0.21.0 h1:AQyQV4dYCvJ7vGmJyKki9+PBdyvhkSd8EIx/qb0AYv4=
+golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
 golang.org/x/sys v0.17.0 h1:25cE3gD+tdBA7lp7QfhuV+rJiE9YXTcS3VG1SqssI/Y=
 golang.org/x/sys v0.17.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.17.0 h1:mkTF7LCd6WGJNL3K1Ad7kwxNfYAW6a8a8QqtMblp/4U=