[BUG] [typescript-angular] Import mappings with same path do not work properly when generating services

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

When defining import mappings with the same path (e.g. --import-mappings=Foo=@foo/bar,Bar=@foo/bar), only one import statement will be generated even if multiple are needed.

Works with models but not with services.

openapi-generator version

7.17.0

OpenAPI declaration file content or url

openapi: 3.1.0
info:
  title: Sample API
  version: 0

paths:
  /users/{foo}/{bar}:
    parameters:
      - schema:
          type: Foo
        name: foo
        in: path
      - schema:
          type: Bar
        name: bar
        in: path
    get:
      responses:
        "200":
          description: "get"
          content:
            application/json:
              schema:
                type: array
                items:
                  type: string

Generation Details

openapi-generator generate -g typescript-angular -i openapi.yaml -o generated --import-mappings=Foo=@foo/bar,Bar=@foo/bar

Steps to reproduce

1. Clone https://github.com/rmeyergh/openapi-generator-typescript-angular-bug
2. Run generate.sh
3. Take a look at generated/api/default.service.ts

Suggest a fix

I don't really have a fix but it look suspicious that in the default mustache template for models {{ #tsImports }} is used while in the api.service.mustache it says {{ #imports }}.

Clone the linked reproduction repository and run generate.sh, then inspect generated/api/default.service.ts. Compare the service template's imports in api.service.mustache with the model template's tsImports handling; done means both Foo and Bar imports are generated when they map to the same path.