all: replace exp/maps and exp/slices with base packages

Since we wrote this code, the maps and slices packages have been promoted to
mainline and expanded, so we no longer need to depend on x/exp for them.

db/db.go

@@ -19,14 +19,14 @@ package db
 import (
 	"errors"
 	"fmt"
+	"slices"
 	"strings"
 	"sync"
 
 	"github.com/tailscale/setec/acl"
 	"github.com/tailscale/setec/audit"
 	"github.com/tailscale/setec/types/api"
 	"github.com/tink-crypto/tink-go/v2/tink"
-	"golang.org/x/exp/slices"
 	"tailscale.com/util/multierr"
 )
 

db/kv.go

@@ -10,12 +10,11 @@ import (
 	"errors"
 	"fmt"
 	"io/fs"
+	"maps"
 	"os"
+	"slices"
 	"sort"
 
-	"golang.org/x/exp/maps"
-	"golang.org/x/exp/slices"
-
 	"github.com/tailscale/setec/types/api"
 	"github.com/tink-crypto/tink-go/v2/aead"
 	"github.com/tink-crypto/tink-go/v2/keyset"
@@ -266,7 +265,7 @@ func (kv *kv) writeGen() uint64 {
 
 // list returns a list of all secret names in kv.
 func (kv *kv) list() []string {
-	ret := maps.Keys(kv.secrets)
+	ret := slices.Collect(maps.Keys(kv.secrets))
 	sort.Strings(ret)
 	return ret
 }