drop x/sys/execabs in favor of os/exec

Per https://go.dev/doc/go1.19#os-exec-path,
Go already has the new safe behavior since version 1.19,
and we now require that version as a minimum.

Author: mvdan

gofmt.go

@@ -17,17 +17,15 @@ import (
 	"io"
 	"io/fs"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"regexp"
 	"runtime"
 	"runtime/pprof"
 	"strings"
 	"sync"
 
-	// TODO: we can soon use os/exec thanks to
-	// https://go.dev/issue/43724
 	"golang.org/x/sync/semaphore"
-	exec "golang.org/x/sys/execabs"
 
 	gformat "mvdan.cc/gofumpt/format"
 	"mvdan.cc/gofumpt/internal/govendor/diff"

main_test.go

@@ -7,11 +7,11 @@ import (
 	"encoding/json"
 	"flag"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"testing"
 
 	qt "github.com/frankban/quicktest"
-	exec "golang.org/x/sys/execabs"
 
 	"github.com/rogpeppe/go-internal/gotooltest"
 	"github.com/rogpeppe/go-internal/testscript"