fix(ci): Resolve workflow-linter self-matching and metadata issues

Author: hyperpolymath

.github/workflows/boj-build.yml

@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: PMPL-1.0-or-later
 name: BoJ Server Build Trigger
 on:
   push:
@@ -8,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
       - name: Trigger BoJ Server (Casket/ssg-mcp)
         run: |
           # Send a secure trigger to boj-server to build this repository