remove after_utc parameter when no signals found (#481)

src/components/Cars/CANSignals/index.jsx

@@ -35,7 +35,7 @@ const Main = ({ vin }) => {
       <Box sx={{ display: "flex", alignItems: "baseline", gap: "8px" }}>
         <span>Searching every</span>
         <DelayController delays={delays} delayIndex={delayIndex} setDelayIndex={setDelayIndex} />
-        <span>seconds for signals sent after {queryDate}.</span>
+        {queryDate && <span>for signals sent after {queryDate}.</span>}
       </Box>
       <Table>
         <TableHead>
@@ -86,7 +86,7 @@ const DelayController = ({
       >
         {delays.map((delay, i) => {
           return (
-            <MenuItem value={i} selected={i === delayIndex} key={delay}>{delay / 1000}</MenuItem>
+            <MenuItem value={i} selected={i === delayIndex} key={delay}>{delay / 1000} seconds</MenuItem>
           );
         })}
       </Select>