fix(McuCard): hide empty fields

Signed-off-by: Pedro Lamas <pedrolamas@gmail.com>

Author: pedrolamas

src/components/widgets/system/McuCard.vue

@@ -16,19 +16,19 @@
 
     <v-simple-table dense>
       <tbody>
-        <tr>
+        <tr v-if="mcuConstants.MCU">
           <th>{{ $t('app.system_info.label.micro_controller') }}</th>
           <td>{{ mcuConstants.MCU }}</td>
         </tr>
-        <tr>
+        <tr v-if="mcuConstants.CLOCK_FREQ">
           <th>{{ $t('app.system_info.label.frequency') }}</th>
           <td>{{ $filters.getReadableFrequencyString(+mcuConstants.CLOCK_FREQ) }}</td>
         </tr>
         <tr v-if="klippyApp.isKalico && mcu.app">
           <th>{{ $t('app.system_info.label.application') }}</th>
           <td>{{ mcu.app }}</td>
         </tr>
-        <tr>
+        <tr v-if="mcu.mcu_version">
           <th>{{ $t('app.system_info.label.version') }}</th>
           <td>{{ mcu.mcu_version }}</td>
         </tr>