async removeMetadata (bookmarkId, metadataId) {
    const result = await db('bookmarks_mapping').where('bookmarkId', bookmarkId).where('metadataId', metadataId).delete()

    if (result) return true
    return false
  }
Remove metadata from bookmark

@param {Int} bookmarkId bookmark id
@param {Int} metadataId metadata id

@returns {Boolean}