chore: improve error handling and output in scripts/update

scripts/update

@@ -11,22 +11,22 @@ source "${project_root}/scripts/lib/shared.sh"
 source "${project_root}/.env"
 
 # pixelfed/pixelfed branch/tag
-pixelfed_release="$1"
+pixelfed_release="${1:?missing argument, the pixelfed release - see https://jippi.github.io/docker-pixelfed/customize/tags/#pixelfed-version}"
 
 # jippi/docker-pixelfed branch/tag
 docker_release="${2-main}"
 
-action_start_newline "fetching docker updates"
+action_start_newline "fetching jippi/docker-pixelfed git updates"
 git fetch origin || action_error_exit "failed"
 action_ok "OK"
 echo
 
-action_start_newline "changing to release branch [${docker_release}]"
+action_start_newline "changing to jippi/docker-pixelfed branch [${docker_release}]"
 git checkout "${docker_release}" || action_error_exit "could not checkout branch ${docker_release}"
 action_ok "OK"
 echo
 
-action_start_newline "pulling updates from remote branch [${docker_release}]"
+action_start_newline "pulling jippi/docker-pixelfed updates from branch [${docker_release}]"
 git pull || action_error_exit "could not update branch ${docker_release}"
 action_ok "OK"
 echo