[Tests] Ensure color codes are stripped in alias tests.

test/common.sh

@@ -11,3 +11,9 @@ assert_not_ok() {
 
   ! $($FUNCTION $@) || die '"'"$FUNCTION $@"'" should have failed, but succeeded'
 }
+
+strip_colors() {
+  while read -r line; do
+    echo "$line" | LC_ALL=C command sed 's/\[[ -?]*[@-~]//g'
+  done
+}