SONAR-22074 enable DownloadOnlyRequired by default

sonar-core/src/main/java/org/sonar/core/config/ScannerProperties.java

@@ -99,7 +99,7 @@ public class ScannerProperties {
         .category(CoreProperties.CATEGORY_GENERAL)
         .subCategory("Performance")
         .type(BOOLEAN)
-        .defaultValue("false")
+        .defaultValue("true")
         .build());
   }
 }

sonar-scanner-engine/src/main/java/org/sonar/scanner/bootstrap/ScannerPluginRepository.java

@@ -68,7 +68,7 @@ public class ScannerPluginRepository implements PluginRepository, Startable {
 
   @Override
   public void start() {
-    shouldLoadOnlyRequiredPluginsOnStart = properties.getBoolean(PLUGIN_LOADING_OPTIMIZATION_KEY).orElse(false);
+    shouldLoadOnlyRequiredPluginsOnStart = properties.getBoolean(PLUGIN_LOADING_OPTIMIZATION_KEY).orElse(true);
     if (!shouldLoadOnlyRequiredPluginsOnStart) {
       LOG.warn("{} is false, so ALL available plugins will be downloaded", PLUGIN_LOADING_OPTIMIZATION_KEY);
       pluginsByKeys = new HashMap<>(installer.installAllPlugins());