Update GitHub Actions workflows

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

Author: alexellis

.github/workflows/build.yaml

@@ -15,7 +15,7 @@ jobs:
       cancel-in-progress: true
     runs-on: actuated-8cpu-12gb
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 1
       - name: Install Go

.github/workflows/publish.yaml

@@ -9,7 +9,7 @@ jobs:
   publish:
     runs-on: actuated-8cpu-12gb
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 1
       - name: Install Go