chore: upgrade lean-update action

Author: pitmonticone

.github/workflows/update-dependencies.yml

@@ -16,8 +16,9 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v4
       - name: Update project
-        uses: Seasawher/lean-update@v0.0.1
+        uses: leanprover-community/lean-update@v0.4.0
         with:
           on_update_succeeds: pr # Create a pull request if the update succeeds
           on_update_fails: issue # Create an issue if the update fails
           update_if_modified: lean-toolchain # Update if there is a new version of the Lean toolchain
+          legacy_update: true    # Executes lake -R -Kenv=dev update instead of lake update