rename src/common -> knotserver-shared

Signed-off-by: tjh <did:plc:65gha4t3avpfpzmvpbwovss7>

update.sh

···
 source src/README.md.sh
 
 for pkgbuild_path in knotserver knotserver-git; do
-  for src in src/common/*.sh; do
+  for src in src/knotserver-shared/*.sh; do
     source ${src}
   done
   for src in src/${pkgbuild_path}/*.sh; do