RTL not working

[alhussien76]

Issue type

Styling

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

• bug report
• feature request
• question about the decisions made in the repository

Issue description

I have used NbThemeModule.forRoot() to change my app to Rtl but it doesn't make any changes.
Current behavior:
nothing happened

Expected behavior:
change the dir attribute in tag its fixed to ltr

Steps to reproduce:

Related code:

insert short code snippets here
export class ThemeModule {
  static forRoot(): ModuleWithProviders<ThemeModule> {
    return {
      ngModule: ThemeModule,
      providers: [
        ...NbThemeModule.forRoot(
          {
            name: 'default',
          },
          [DEFAULT_THEME, COSMIC_THEME, CORPORATE_THEME, DARK_THEME],
          null,
          NbLayoutDirection.RTL
        ).providers,
      ],
    };
  }
}

Other information:

npm, node, OS, Browser

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Angular, Nebular

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    "@nebular/eva-icons": "5.0.0",
    "@nebular/security": "5.0.0",
    "@nebular/theme": "5.0.0",
-->