test: add auto-download of stemcells for local test

acceptance-tests/run-local.sh

@@ -31,16 +31,28 @@ docker_mac_check_cgroupsv1() {
 
 check_required_files() {
   REQUIRED_FILE_PATTERNS=(
-    ../ci/scripts/bpm/bpm-release-*.tgz
-    ../ci/scripts/stemcell/bosh-stemcell-*-ubuntu-jammy-*.tgz
-    ../ci/scripts/stemcell-bionic/bosh-stemcell-*-ubuntu-bionic-*.tgz
+    ../ci/scripts/bpm/bpm-release-*.tgz!https://bosh.io/d/github.com/cloudfoundry/bpm-release
+    ../ci/scripts/stemcell/bosh-stemcell-*-ubuntu-jammy-*.tgz!https://bosh.io/d/stemcells/bosh-warden-boshlite-ubuntu-jammy-go_agent
+    ../ci/scripts/stemcell-bionic/bosh-stemcell-*-ubuntu-bionic-*.tgz!https://bosh.io/d/stemcells/bosh-warden-boshlite-ubuntu-bionic-go_agent
   )
 
-  for pattern in "${REQUIRED_FILE_PATTERNS[@]}"; do
-    if [ ! -f "$pattern" ]; then
-      echo "Required file not found: {$pattern}"
-      exit 1
+  for entry in "${REQUIRED_FILE_PATTERNS[@]}"; do
+    # shellcheck disable=SC2206
+    tuple=( ${entry//!/ } )
+
+    pattern=${tuple[0]}
+    url=${tuple[1]}
+
+    if [ -f "$pattern" ]; then
+      continue
     fi
+
+    (
+      cd "$(realpath "$SCRIPT_DIR/$(dirname "$pattern")")"
+      resolved=$(curl -s --write-out '%{redirect_url}' "$url" | tail -n1)
+      curl --remote-name --remote-header-name --location "$resolved"
+    )
+
   done
 }