NbAuthSimpleInterceptor does not add Bearer prefix to HTTP header

[willydee]

Issue type

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

• bug report
• feature request

Issue description

Current behavior:
Using NbPasswordAuthStrategy and the accompanying NbAuthSimpleInterceptor, the received token is inserted as HTTP header like so:
Authorization: 3b023126-a007-422e-9838-839871aae08b

Expected behavior:
I would need it to be:
Authorization: Bearer 3b023126-a007-422e-9838-839871aae08b

Steps to reproduce:
I generally followed the tutorial for NbPasswordAuthStrategy in the Nebular vnext Docs

Related code:
As a workaround I managed to configure a custom getter, like so:

NbAuthModule.forRoot({
  strategies: [
    NbPasswordAuthStrategy.setup({
      token: {
        key: 'token',
        getter: (_module: string, response: HttpResponse<{ token: string }>) =>
          `Bearer ${response.body?.token ?? ''}`,
      },
      // ...
    }),
  ],
});

Other information:

There is a (quite dated) Stackoverflow issue describing a similar issue with NbAuthJWTInterceptor, where the Bearer prefix is added in a hardcoded way instead. I guess it would be useful to generally make this prefix configurable (with sensible default that won't break existing apps).

npm, node, OS, Browser

Node v16.19.0
yarn: 1.22.19  
OS: EndeavourOS/ArchLinux x64 (rolling)
Browser: Firefox 108.0.1

Angular, Nebular

@angular/core: 15.0.0
@nebular/auth: 10.0.0