Bump actions/checkout from 3 to 4

Set dependabot for the main branch

.github/dependabot.yml

@@ -7,6 +7,6 @@ updates:
   directory: "/"
   schedule:
    interval: "monthly"
-  target-branch: "develop"
+  # target-branch: "develop"
   labels:
   - "dependencies"

.github/workflows/build.yml

@@ -17,7 +17,7 @@ jobs:
   steps:
 
   - name: Clone sfall
-    uses: actions/checkout@v3
+    uses: actions/checkout@v4
 
   # Action is used twice for self-testing only
   # DevXP build results are intentionally *not* included in artifact

.github/workflows/gh-pages.yml

@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Setup Python
         uses: actions/setup-python@v4