feat: Add didcommv2 extra to Dockerfile for builds

It was requested in today's ACA-Pug by @PatStLouis to add the didcommv2
extra to the docker images that are built, and multiple people in the
call agreed with the idea. Myself included.

Signed-off-by: Colton Wolkins (Indicio work address) <colton@indicio.tech>

docker/Dockerfile

@@ -13,7 +13,7 @@ FROM python:${python_version}-slim-bullseye AS main
 ARG uid=1001
 ARG user=aries
 ARG acapy_version
-ARG acapy_reqs=[askar,bbs]
+ARG acapy_reqs=[askar,bbs,didcommv2]
 
 ENV HOME="/home/$user" \
     APP_ROOT="$HOME" \