Reintroduce "intro: format link with .Lk"

This reverts commit 8089c0c3820cbcfe0f267e507cc18b4ffd057896.

The bug is groff's and Debian is working to fix it.  We don't need to
work around it anymore.

diff --git a/doc/man/man3/intro.3monocypher b/doc/man/man3/intro.3monocypher
index 507ac375a5569f4c7a63ca55947a633cb177cecb..3eb4415cddd420b3567226fd3d97c302258f5e54 100644 (file)
--- a/doc/man/man3/intro.3monocypher
+++ b/doc/man/man3/intro.3monocypher
@@ -151,7 +151,8 @@ Cryptographic libraries are easy to misuse.
 Even Monocypher allows a number of fatal mistakes.
 .Pp
 Users should follow a formal introduction to cryptography.
-We currently recommend the https://www.crypto101.io/ online course.
+We currently recommend the
+.Lk https://www.crypto101.io/ "Crypto 101 online course" .
 .Ss Random number generation
 Use the facilities of your operating system.
 Avoid user space random number generators.