[Misc] Improve environment handling during tests

  * Fix tests failure in extension handler

xwiki-platform-core/xwiki-platform-extension/xwiki-platform-extension-handlers/xwiki-platform-extension-handler-xar/src/test/java/org/xwiki/extension/xar/internal/handler/WikiEventListenerTest.java

@@ -24,6 +24,7 @@
 import org.junit.Rule;
 import org.junit.Test;
 import org.xwiki.bridge.event.WikiCopiedEvent;
+import org.xwiki.environment.Environment;
 import org.xwiki.extension.DefaultExtensionDependency;
 import org.xwiki.extension.ExtensionId;
 import org.xwiki.extension.InstallException;
@@ -67,6 +68,7 @@ public void afterComponent() throws Exception
     {
         this.wikiDescriptorManager =
             this.repositoryUtil.getComponentManager().registerMockComponent(WikiDescriptorManager.class);
+        this.repositoryUtil.getComponentManager().unregisterComponent(Environment.class, "default");
     }
 
     @Before

xwiki-platform-core/xwiki-platform-extension/xwiki-platform-extension-handlers/xwiki-platform-extension-handler-xar/src/test/java/org/xwiki/extension/xar/internal/repository/XarInstalledExtensionRepositoryTest.java

@@ -25,6 +25,7 @@
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
+import org.xwiki.environment.Environment;
 import org.xwiki.extension.ExtensionId;
 import org.xwiki.extension.ResolveException;
 import org.xwiki.extension.repository.InstalledExtensionRepository;
@@ -54,6 +55,7 @@ public class XarInstalledExtensionRepositoryTest
     public void afterComponent() throws Exception
     {
         this.repositoryUtil.getComponentManager().registerMockComponent(WikiDescriptorManager.class);
+        this.repositoryUtil.getComponentManager().unregisterComponent(Environment.class, "default");
     }
 
     @Before