use checkout@v4

(cherry picked from commit 4a62211)

Author: mrshmllow

.github/workflows/build.yml

@@ -1,6 +1,7 @@
 name: build
 on:
   workflow_dispatch:
+  pull_request:
   push:
     braches:
       - main
@@ -13,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - uses: cachix/install-nix-action@v27
       - name: Flake Check
         run: nix flake check --impure
@@ -28,7 +29,7 @@ jobs:
           - neoforge
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
       - name: Setup Java
         uses: actions/setup-java@v4
         with: