ci: simplify gofmt hook to use native pre-commit file filtering

Let pre-commit pass staged Go files to gofmt instead of scanning the
entire tree. Uses gofmt -w to auto-fix formatting in place.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Generated-by: Claude

rh-pre-commit.version: 2.4.0
rh-pre-commit.check-secrets: ENABLED

Author: jhutar

.pre-commit-config.yaml

@@ -79,10 +79,9 @@ repos:
     hooks:
       - id: go-fmt
         name: gofmt
-        entry: bash -c 'out=$(gofmt -l .); [ -z "$out" ] || { echo "$out"; exit 1; }'
+        entry: gofmt -w
         language: system
         types: [go]
-        pass_filenames: false
 
       - id: go-vet
         name: go vet