Bump the version for those github action in the workflow file.

Hope this can prevent us from the update of github action for a while.

Author: kito-cheng

.github/workflows/build.yml

@@ -13,7 +13,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
 
       - name: Install packages
         run: sudo apt-get update && sudo apt-get install -y make ruby
@@ -25,7 +25,7 @@ jobs:
         run: make
 
       - name: Upload artifact
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: riscv-abi.pdf
           path: riscv-abi.pdf
@@ -36,7 +36,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Download artifact
-        uses: actions/download-artifact@v4.1.7
+        uses: actions/download-artifact@v4
         with:
           name: riscv-abi.pdf
           path: ./
@@ -73,7 +73,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Download artifact
-        uses: actions/download-artifact@v4.1.7
+        uses: actions/download-artifact@v4
         with:
           name: riscv-abi.pdf
           path: ./