Fix issue with Container file ARGs

Containerfile.cp

@@ -12,7 +12,7 @@ ARG BASE_IMAGE_URL=ghcr.io/ublue-os/cinnamon-main
 FROM ${BASE_IMAGE_URL}:${FEDORA_MAJOR_VERSION}
 
 ARG USER_NAME=cp
-ARG USR_DIR=usr-${USER_NAME}
+ARG USER_DIR=usr-${USER_NAME}
 
 # The default recipe set to the recipe's default filename
 # so that `podman build` should just work for many people.
@@ -26,7 +26,7 @@ ARG RECIPE=recipe-c.yml
 # for manual overrides and editing by the machine's admin AFTER installation!
 # See issue #28 (https://github.com/ublue-os/startingpoint/issues/28).
 COPY usr/ /usr
-COPY ${USR_DIR}/ /usr
+COPY ${USER_DIR}/ /usr
 
 # Copy the recipe that we're building.
 COPY ${RECIPE} /usr/share/ublue-os/recipe.yml