Update MTM no data tab translation

plugins/JsTrackerInstallCheck/JsTrackerInstallCheck.php

@@ -30,7 +30,7 @@ public function registerEvents()
 
     public function getClientSideTranslationKeys(&$translationKeys)
     {
-        $translationKeys[] = 'JsTrackerInstallCheck_TestInstallationDescription';
+        $translationKeys[] = 'JsTrackerInstallCheck_OptionalTestInstallationDescription';
         $translationKeys[] = 'JsTrackerInstallCheck_TestInstallationBtnText';
         $translationKeys[] = 'JsTrackerInstallCheck_JsTrackingCodeInstallCheckSuccessMessage';
         $translationKeys[] = 'JsTrackerInstallCheck_JsTrackingCodeInstallCheckFailureMessage';

plugins/JsTrackerInstallCheck/lang/en.json

@@ -1,7 +1,7 @@
 {
     "JsTrackerInstallCheck": {
         "PluginDescription": "Validate whether the tracking code has been installed on your site and that it can send tracking requests back to your Matomo instance",
-        "TestInstallationDescription": "To test that the tracking code is able to send requests to your Matomo instance, enter the exact URL you are tracking and click on \"Test installation\". A new tab will open, and should close within 10 seconds.",
+        "OptionalTestInstallationDescription": "Optional: To test that the tracking code is able to send requests to your Matomo instance, enter the exact URL you are tracking and click on \"Test installation\". A new tab will open, and should close within 10 seconds.",
         "TestInstallationBtnText": "Test installation",
         "JsTrackingCodeInstallCheckSuccessMessage": "The tracking code is installed successfully! This screen will disappear as soon as some data is tracked for your website.",
         "JsTrackingCodeInstallCheckFailureMessage": "Tracking code verification failed. Please verify that you have installed the code correctly. %1$sLearn more%2$s.",

plugins/JsTrackerInstallCheck/vue/src/JsTrackerInstallCheck/JsTrackerInstallCheck.vue

@@ -1,5 +1,5 @@
 <template>
-    <span>{{ translate('JsTrackerInstallCheck_TestInstallationDescription') }}</span>
+    <span>{{ translate('JsTrackerInstallCheck_OptionalTestInstallationDescription') }}</span>
     <div class="jsTrackerInstallCheck">
       <div class="row testInstallFields">
         <div class="col s2">