Use slices package from the stdlib when possible (#5360)

* Use slices from the stdlib when possible

* Add some unit tests

* More small tweaks + add benchmark func

pkg/sqlite/setup_test.go

@@ -10,13 +10,13 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"slices"
 	"strconv"
 	"testing"
 	"time"
 
 	"github.com/stashapp/stash/internal/manager/config"
 	"github.com/stashapp/stash/pkg/models"
-	"github.com/stashapp/stash/pkg/sliceutil"
 	"github.com/stashapp/stash/pkg/sqlite"
 	"github.com/stashapp/stash/pkg/txn"
 
@@ -1585,7 +1585,7 @@ func getTagMarkerCount(id int) int {
 	count := 0
 	idx := indexFromID(tagIDs, id)
 	for _, s := range markerSpecs {
-		if s.primaryTagIdx == idx || sliceutil.Contains(s.tagIdxs, idx) {
+		if s.primaryTagIdx == idx || slices.Contains(s.tagIdxs, idx) {
 			count++
 		}
 	}