Skip broken PKCS overlong message test

TestOverlongMessagePKCS1v15 tests that an error is returned on an
invalid message. We can safely skip the test, as the constraint doesn't
apply when using OpenSSL versions with implicit rejection in
RSA PKCS#1 v1.5, which would return a random message instead of an error.

patches/004-skip-pkcs-test.patch

@@ -0,0 +1,15 @@
+diff --git a/src/crypto/rsa/pkcs1v15_test.go b/src/crypto/rsa/pkcs1v15_test.go
+index f6afc363ea..c164ec5706 100644
+--- a/src/crypto/rsa/pkcs1v15_test.go
++++ b/src/crypto/rsa/pkcs1v15_test.go
+@@ -245,6 +245,10 @@ func TestVerifyPKCS1v15(t *testing.T) {
+ }
+
+ func TestOverlongMessagePKCS1v15(t *testing.T) {
++	// OpenSSL now returns a random string instead of an error
++	if boring.Enabled() {
++		t.Skip("Not relevant in boring mode")
++	}
+ 	ciphertext := decodeBase64("fjOVdirUzFoLlukv80dBllMLjXythIf22feqPrNo0YoIjzyzyoMFiLjAc/Y4krkeZ11XFThIrEvw\nkRiZcCq5ng==")
+ 	_, err := DecryptPKCS1v15(nil, rsaPrivateKey, ciphertext)
+ 	if err == nil {