packages: simplify the setup to use the same as upgrades

the packages tests control which Forgejo version they run against so
they can test a feature on version X+1 and not on version X

packages/alpine.sh

@@ -2,16 +2,18 @@
 # Copyright 2024 The Forgejo Authors
 # SPDX-License-Identifier: MIT
 
-SELF_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+function test_packages_alpine_v1.21() {
+    stop_daemon forgejo
+    reset_forgejo $PACKAGES_DIR/alpine-app.ini
+    start_forgejo 1.21
 
-source $SELF_DIR/../lib/lib.sh
-
-function main() {
-    local d=$SELF_DIR/alpine
-    local token=$(cat $DIR/forgejo-token)
-    local url=$(cat $DIR/forgejo-url)
+    local d=$PACKAGES_DIR/alpine
+    local token=$(cat $DIR/forgejo-curl/token)
+    local url=http://${HOST_PORT}
 
     docker run --rm --volume $d:$d:ro --workdir $d docker.io/alpine:3.19 ash -c "./test.sh $url $token"
 }
 
-"${@:-main}"
+function test_packages_alpine() {
+    test_packages_alpine_v1.21
+}