Cleanup openapi generation (#4331)

Co-authored-by: oauth <woodpecker-bot@obermui.de>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: 6543 <6543@obermui.de>

tools/tools.go

@@ -0,0 +1,23 @@
+// Copyright 2024 Woodpecker Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build tools
+// +build tools
+
+package main
+
+import (
+	_ "github.com/getkin/kin-openapi/cmd/validate"
+	_ "github.com/swaggo/swag/cmd/swag"
+)