docs/website: adjust link to Buildroot training course

The previous course has ended, announce the next one.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

docs/website/docs.html

@@ -113,9 +113,9 @@
 	      The next online public training course on Buildroot
 	      organized
 	      by <a href="https://www.bootlin.com">Bootlin</a> will
-	      take place on March 8-11, 2021, with Thomas Petazzoni as
+	      take place from May 31 to June 4, 2021, with Thomas Petazzoni as
 	      trainer. <a href="https://bootlin.com/training/buildroot/">Infos</a>
-	      and <a href="https://www.eventbrite.fr/e/bootlin-embedded-linux-development-with-buildroot-training-seminar-tickets-108855638144">registration</a>.
+	      and <a href="https://www.eventbrite.com/e/bootlin-embedded-linux-development-with-buildroot-training-seminar-tickets-145276318379">registration</a>.
 	    </div>
 	  </div>
 	</div>