Chore: Update CI workflow

Author: deathaxe

.github/workflows/lint.yml

@@ -15,6 +15,6 @@ jobs:
     name: Flake8
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - uses: TrueBrain/actions-flake8@v2

.github/workflows/syntax.yml

@@ -40,7 +40,7 @@ jobs:
             continue_on_error: true
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: SublimeText/syntax-test-action@v2
         with:
           build: ${{ matrix.build }}