Remove Z from timestamp format - unnecessary for consistent server timezone

src/logging.rs

@@ -7,7 +7,7 @@ struct GeminiTimeFormat;
 impl FormatTime for GeminiTimeFormat {
     fn format_time(&self, w: &mut tracing_subscriber::fmt::format::Writer<'_>) -> std::fmt::Result {
         let now = time::OffsetDateTime::now_utc();
-        write!(w, "{}-{:02}-{:02}T{:02}:{:02}:{:02}Z",
+        write!(w, "{}-{:02}-{:02}T{:02}:{:02}:{:02}",
                now.year(), now.month() as u8, now.day(),
                now.hour(), now.minute(), now.second())
     }