* a regex pattern matches the query.
     *
     * @param queryPlaceHolder the placeholder string to be replaced with the query (default: "__QUERY__")
     */
    public void setQueryPlaceHolder(final String queryPlaceHolder) {
        this.queryPlaceHolder = queryPlaceHolder;
    }

    }

    @Test
    public void test_setQueryPlaceHolder() {
        assertEquals("__QUERY__", relatedContentHelper.queryPlaceHolder);

        relatedContentHelper.setQueryPlaceHolder("{{QUERY}}");
        assertEquals("{{QUERY}}", relatedContentHelper.queryPlaceHolder);

        // Test with the new placeholder
        List<RelatedContent> testData = new ArrayList<>();