doc/developer: update link to "sign-off" info

Found by Hendrik Schreiber.

Signed-off-by: Lou Logan <lou@lrcd.com>

doc/developer.texi

@@ -562,9 +562,9 @@ Does @code{make fate} pass with the patch applied?
 Was the patch generated with git format-patch or send-email?
 
 @item
-Did you sign off your patch? (git commit -s)
-See @url{http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=blob_plain;f=Documentation/SubmittingPatches} for the meaning
-of sign off.
+Did you sign-off your patch? (@code{git commit -s})
+See @uref{https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/plain/Documentation/process/submitting-patches.rst, Sign your work} for the meaning
+of @dfn{sign-off}.
 
 @item
 Did you provide a clear git commit log message?