chore: don't log non-error message at error level

When walking the tree for creating the search index, ignore "not found"
errors. Search indexing happens asynchronously so the underlying space,
file or folder might just not exist anymore when the indexing starts.

services/search/pkg/search/service.go

@@ -2,6 +2,7 @@ package search
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"path/filepath"
 	"sort"
@@ -487,6 +488,12 @@ func (s *Service) IndexSpace(spaceID *provider.StorageSpaceId, forceRescan bool)
 	}()
 	err = w.Walk(ownerCtx, &rootID, func(wd string, info *provider.ResourceInfo, err error) error {
 		if err != nil {
+			var notFoundErr errtypes.IsNotFound
+			if errors.As(err, &notFoundErr) {
+				// The resource disappeared while walking the tree. E.g. the underlying file/directory/space
+				// might just have been deleted meanwhile. We can just ignore this error.
+				return nil
+			}
 			s.logger.Error().Err(err).Msg("error walking the tree")
 			return err
 		}