Upgrade checkout action to version 4 and simplify setup

Author: tomast1337

.github/workflows/tests.yml

@@ -15,16 +15,14 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - name: Checkout code
-        uses: actions/checkout@v3
-
-      - name: Set up Bun
-        run: |
-          curl -fsSL https://bun.sh/install | bash
-          echo "${HOME}/.bun/bin" >> $GITHUB_PATH
-
-      - name: Install dependencies
-        run: bun install
+      - name: Checkout
+        uses: actions/checkout@v4
+      
+      - name: Install bun
+        uses: oven-sh/setup-bun@v2
+      
+      - name: Install dependencies # (assuming your project has dependencies)
+        run: bun install # You can use npm/yarn/pnpm instead if you prefer
 
       - name: Run tests
         run: bun run test