fix(schematics): missing routing module in sidemenu template (#3695)

schematics/ng-generate/side-menu/files/src/app/pages/welcome/welcome-routing.module.ts.template

@@ -0,0 +1,13 @@
+import { NgModule } from '@angular/core';
+import { Routes, RouterModule } from '@angular/router';
+import { WelcomeComponent } from './welcome.component';
+
+const routes: Routes = [
+  { path: '', component: WelcomeComponent },
+];
+
+@NgModule({
+  imports: [RouterModule.forChild(routes)],
+  exports: [RouterModule]
+})
+export class WelcomeRoutingModule { }

schematics/ng-generate/side-menu/files/src/app/pages/welcome/welcome.module.ts.template

@@ -1,8 +1,13 @@
 import { NgModule } from '@angular/core';
+
+import { WelcomeRoutingModule } from './welcome-routing.module';
+
 import { WelcomeComponent } from './welcome.component';
 
+
 @NgModule({
-  declarations: [ WelcomeComponent ],
-  exports: [ WelcomeComponent ]
+  imports: [WelcomeRoutingModule],
+  declarations: [WelcomeComponent],
+  exports: [WelcomeComponent]
 })
 export class WelcomeModule { }