Revert "[dashboard] Downtime in-app announcements (#18761)"

This reverts commit cebee56, modulo some fixes we want to keep.

components/dashboard/src/app/AppRoutes.tsx

@@ -39,7 +39,6 @@ import PersonalAccessTokenCreateView from "../user-settings/PersonalAccessTokens
 import { CreateWorkspacePage } from "../workspaces/CreateWorkspacePage";
 import { WebsocketClients } from "./WebsocketClients";
 import { BlockedEmailDomains } from "../admin/BlockedEmailDomains";
-import { AppNotifications } from "../AppNotifications";
 
 const Workspaces = React.lazy(() => import(/* webpackPrefetch: true */ "../workspaces/Workspaces"));
 const Account = React.lazy(() => import(/* webpackPrefetch: true */ "../user-settings/Account"));
@@ -122,7 +121,6 @@ export const AppRoutes = () => {
         <Route>
             <div className="container">
                 <Menu />
-                <AppNotifications />
                 <Switch>
                     <Route path="/new" exact component={CreateWorkspacePage} />
                     <Route path={projectsPathNew} exact component={NewProject} />

components/dashboard/src/data/featureflag-query.ts

@@ -15,7 +15,6 @@ const featureFlags = {
     publicApiExperimentalWorkspaceService: false,
     personalAccessTokensEnabled: false,
     oidcServiceEnabled: false,
-    scheduled_downtime_notification: false,
     // Default to true to enable on gitpod dedicated until ff support is added for dedicated
     orgGitAuthProviders: true,
     userGitAuthProviders: false,

components/proxy/conf/Caddyfile

@@ -195,22 +195,6 @@ https://{$GITPOD_DOMAIN} {
 	import ssl_configuration
 	import security_headers
 
-	# maintenance redirect (+ redirect away afterwards)
-	@maintenance_redirect {
-		expression `'{$MAINTENANCE_REDIRECT}' == 'true'`
-		not path /maintenance/*
-	}
-	handle @maintenance_redirect {
-		redir https://{$GITPOD_DOMAIN}/maintenance/index.html 307
-	}
-	@maintenance_done_redirect {
-		expression `'{$MAINTENANCE_REDIRECT}' != 'true'`
-		path /maintenance/*
-	}
-	handle @maintenance_done_redirect {
-		redir https://{$GITPOD_DOMAIN}/workspaces permanent
-	}
-
 	@proxy_server_public_api path /public-api/gitpod.experimental.v1.HelloService*
 	handle @proxy_server_public_api {
 		uri strip_prefix /public-api