repository: remove redundant cleanup code

The temp files used by the packer manager are either delete after
creation (unix) or marked as delete on close (windows). Thus, no
explicit cleanup is necessary.

internal/repository/packer_manager.go

@@ -6,7 +6,6 @@ import (
 	"crypto/sha256"
 	"io"
 	"os"
-	"runtime"
 	"sync"
 
 	"github.com/restic/restic/internal/backend"
@@ -186,14 +185,6 @@ func (r *Repository) savePacker(ctx context.Context, t restic.BlobType, p *packe
 		return errors.Wrap(err, "close tempfile")
 	}
 
-	// on windows the tempfile is automatically deleted on close
-	if runtime.GOOS != "windows" {
-		err = fs.RemoveIfExists(p.tmpfile.Name())
-		if err != nil {
-			return errors.WithStack(err)
-		}
-	}
-
 	// update blobs in the index
 	debug.Log("  updating blobs %v to pack %v", p.Packer.Blobs(), id)
 	r.idx.StorePack(id, p.Packer.Blobs())