Use an explicit permissions block (#11)

This is to let us drop the default `GITHUB_TOKEN` permissions

Signed-off-by: Matt Moore <mattmoor@chainguard.dev>

.github/workflows/publish.yaml

@@ -8,11 +8,13 @@ jobs:
   publish:
     name: Publish
     runs-on: ubuntu-latest
+    permissions:
+      packages: write # To publish container images
     steps:
       - uses: actions/setup-go@0c52d547c9bc32b1aa3301fd7a9cb496313a4491 # v5.0.0
         with:
           go-version: 1.18
       - uses: actions/checkout@8ade135a41bc03ea155e62e844d188df1ea18608 # v4.1.0
 
       - uses: ko-build/setup-ko@ace48d793556083a76f1e3e6068850c1f4a369aa # v0.6
-      - run: ko publish ./
+      - run: ko build .