[fork_check] Clean up unused file

I introduced this file in
commit 7fafae0f3d68b0a57a4532f7e2bd0fed7a2a1bf3, then renamed it during
code review (to "internal/go_checks/fork_check/main.go") but forgot to
delete it from the original location.

Change-Id: I7e2f1c49f0b3730cd441a673baa06a4e1162f8d9
Reviewed-on: https://fuchsia-review.googlesource.com/c/shac-project/shac/+/911232
Fuchsia-Auto-Submit: Oliver Newman <olivernewman@google.com>
Commit-Queue: Auto-Submit <auto-submit@fuchsia-infra.iam.gserviceaccount.com>
Reviewed-by: Danny Rosen <dannyrosen@google.com>
diff --git a/cmd/fork_check/main.go b/cmd/fork_check/main.go
deleted file mode 100644
index 56eb61c..0000000
--- a/cmd/fork_check/main.go
+++ /dev/null
@@ -1,81 +0,0 @@
-// Copyright 2023 The Shac 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.
-
-// Package main implements a check that the os/exec.Cmd Start() and Run()
-// functions aren't called directly.
-//
-// Instead, callers should use the execsupport package.
-package main
-
-import (
-	"go/ast"
-
-	"golang.org/x/tools/go/analysis"
-	"golang.org/x/tools/go/analysis/multichecker"
-)
-
-func run(pass *analysis.Pass) (any, error) {
-	for _, f := range pass.Files {
-		ast.Inspect(f, func(n ast.Node) bool {
-			if n == nil {
-				return false
-			}
-			call, ok := n.(*ast.CallExpr)
-			if !ok {
-				return true
-			}
-			selector, ok := call.Fun.(*ast.SelectorExpr)
-			if !ok {
-				return true
-			}
-			funcName := selector.Sel.Name
-			if funcName != "Start" && funcName != "Run" {
-				return true
-			}
-
-			var obj *ast.Ident
-			switch o := selector.X.(type) {
-			case *ast.Ident:
-				obj = o
-			case *ast.SelectorExpr:
-				obj = o.Sel
-			default:
-				return true
-			}
-
-			// Skip function calls that aren't struct methods.
-			if obj == nil {
-				return true
-			}
-
-			typ := pass.TypesInfo.ObjectOf(obj).Type()
-			if typ.String() == "*os/exec.Cmd" {
-				pass.Reportf(n.Pos(), "do not call %s.%s() directly, use execsupport.%s(%s) instead",
-					obj.Name, funcName, funcName, obj.Name)
-			}
-			return false
-		})
-	}
-	return nil, nil
-}
-
-func main() {
-	multichecker.Main(
-		&analysis.Analyzer{
-			Name: "directexec",
-			Doc:  "do not call os/exec.Cmd Start or Run functions directly",
-			Run:  run,
-		},
-	)
-}