refactor: replace golang.org/x/exp/slices with slices (#16772)

The experimental functions in `golang.org/x/exp/slices` are now
available in the standard library since Go 1.21.

Reference: https://go.dev/doc/go1.21#slices

Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>

cli/configssh.go

@@ -11,6 +11,7 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"slices"
 	"strconv"
 	"strings"
 
@@ -19,7 +20,6 @@ import (
 	"github.com/pkg/diff"
 	"github.com/pkg/diff/write"
 	"golang.org/x/exp/constraints"
-	"golang.org/x/exp/slices"
 	"golang.org/x/xerrors"
 
 	"github.com/coder/coder/v2/cli/cliui"