Do not store state of Welcome page

Signed-off-by: Vitaliy Gulyy <vgulyy@redhat.com>

plugins/welcome-plugin/src/welcome-plugin.ts

@@ -113,8 +113,6 @@ export async function addPanel(context: theia.PluginContext): Promise<void> {
 export function start(context: theia.PluginContext): void {
     let showWelcomePage: boolean | undefined = true;
 
-    theia.window.registerWebviewPanelSerializer(welcomePageViewType, new WelcomePageSerializer(context));
-
     const configuration = theia.workspace.getConfiguration(Settings.CHE_CONFIGURATION);
     if (configuration) {
         showWelcomePage = configuration.get(Settings.SHOW_WELCOME_PAGE);
@@ -130,14 +128,3 @@ export function start(context: theia.PluginContext): void {
 
 export function stop(): void {
 }
-
-export class WelcomePageSerializer implements theia.WebviewPanelSerializer {
-
-    constructor(readonly context: theia.PluginContext) {
-    }
-
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    async deserializeWebviewPanel(webviewPanel: theia.WebviewPanel, state: any): Promise<void> {
-        webviewPanel.webview.html = await getHtmlForWebview(this.context);
-    }
-}