[#606] Make log tags more explicit

Signed-off-by: Alex Vanin <a.vanin@yadro.com>

api/cache/accessbox.go

@@ -67,7 +67,7 @@ func (o *AccessBoxCache) Get(accessKeyID string) *AccessBoxCacheValue {
 	result, ok := entry.(*AccessBoxCacheValue)
 	if !ok {
 		o.logger.Warn(logs.InvalidCacheEntryType, zap.String("actual", fmt.Sprintf("%T", entry)),
-			zap.String("expected", fmt.Sprintf("%T", result)))
+			zap.String("expected", fmt.Sprintf("%T", result)), logs.TagField(logs.TagDatapath))
 		return nil
 	}