Remove DenylistImports (#23)

`DenylistImports` will be redundant once [gitea/pull/22412](https://github.com/go-gitea/gitea/pull/22412) has been merged.

Reviewed-on: https://gitea.com/gitea/gitea-vet/pulls/23
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-by: John Olheiser <john+gitea@jolheiser.com>
Co-authored-by: Jason Song <i@wolfogre.com>
Co-committed-by: Jason Song <i@wolfogre.com>

checks/denylisted-imports.go

@@ -1,46 +0,0 @@
-// Copyright 2022 The Gitea Authors. All rights reserved.
-// SPDX-License-Identifier: MIT
-
-package checks
-
-import (
-	"strings"
-
-	"golang.org/x/tools/go/analysis"
-)
-
-var (
-	deniedImports   = []string{"io/ioutil", "encoding/json", "gitea.com/gitea/go-crypto"}
-	DenylistImports = &analysis.Analyzer{
-		Name: "denylist_imports",
-		Doc:  "check for denied imports",
-		Run:  runDenylistImports,
-	}
-)
-
-func runDenylistImports(pass *analysis.Pass) (interface{}, error) {
-	for _, file := range pass.Files {
-		for _, im := range file.Imports {
-			val := im.Path.Value
-			val = strings.TrimPrefix(val, `"`)
-			val = strings.TrimSuffix(val, `"`)
-			for _, deniedImport := range deniedImports {
-				if strings.HasPrefix(val, deniedImport) {
-					// Allow a exemption when there is a comment 'Allow "package_name" import'
-					allowed := false
-					for _, comment := range file.Comments {
-						if strings.Contains(comment.Text(), "Allow \""+val+"\" import") {
-							allowed = true
-							break
-						}
-					}
-
-					if !allowed {
-						pass.Reportf(im.Path.Pos(), `"`+val+"\" is not allowed to be imported")
-					}
-				}
-			}
-		}
-	}
-	return nil, nil
-}

main.go

@@ -11,7 +11,6 @@ import (
 
 func main() {
 	unitchecker.Main(
-		checks.DenylistImports,
 		checks.Imports,
 		checks.License,
 		checks.Migrations,