With RTL support turned on and sidebar placed on the right site breaks on mobile view

### Issue type

**I'm submitting a ...** (check one with "x")

* [ x ] bug report
* [ ] feature request

### Issue description

**Current behavior:**
With RTL support turned on and sidebar placed on the right site breaks on mobile view

works fine when used in wide screens

**Expected behavior:**
Should work nicely on mobile devices when sidebar on the right side

**Steps to reproduce:**
ThemeModule ==>
add these lines

export class ThemeModule {
static forRoot(): ModuleWithProviders {
return {
ngModule: ThemeModule,
providers: [
...NbThemeModule.forRoot(
{name: 'default',
},
[
DEFAULT_THEME
],
DEFAULT_MEDIA_BREAKPOINTS,
NbLayoutDirection.RTL
).providers,
],
};
}
}

also add "start" to

### Other information:
@akveo/ng2-completer": "^9.0.1",
"@angular/animations": "^12.1.0",
"@angular/cdk": "12.1.0",
"@angular/common": "^12.1.0",
"@angular/compiler": "^12.1.0",
"@angular/core": "^12.1.0",
"@angular/forms": "^12.1.0",
"@angular/material": "^12.1.0",
"@angular/platform-browser": "^12.1.0",
"@angular/platform-browser-dynamic": "^12.1.0",
"@angular/router": "^12.1.0",
"@nebular/auth": "8.0.0",
"@nebular/eva-icons": "^8.0.0",
"@nebular/security": "8.0.0",
"@nebular/theme": "8.0.0",