fix(plugin): Add new abstract methods

Mandatory since Composer 2.0

Author: gaetan-hexadog

src/ThemeInstallerPlugin.php

@@ -17,4 +17,20 @@ public function activate(Composer $composer, IOInterface $io)
 
         $composer->getInstallationManager()->addInstaller($installer);
     }
+
+	/**
+     * {@inheritdoc}
+     */
+	public function deactivate(Composer $composer, IOInterface $io)
+	{
+		// 
+	}
+
+	/**
+     * {@inheritdoc}
+     */
+	public function uninstall(Composer $composer, IOInterface $io)
+	{
+		// 
+	}
 }