remove unfinished timezone engine

src/engines/answer/timezone.rs

@@ -1,21 +0,0 @@
-use std::{cell::Cell, sync::LazyLock};
-
-use fend_core::SpanKind;
-
-use crate::engines::EngineResponse;
-
-use super::regex;
-
-pub fn request(query: &str) -> EngineResponse {
-    let query = clean_query(query.to_string());
-
-    let Some(result_html) = evaluate(&query, true) else {
-        return EngineResponse::new();
-    };
-
-    EngineResponse::answer_html(format!(
-        r#"<p class="answer-calc-query">{query} =</p>
-<h3><b>{result_html}</b></h3>"#,
-        query = html_escape::encode_text(&query),
-    ))
-}