typescript-fetch: fix return type of primitive value (#4028)

* Update apis.mustache

Fixes #3709 and #2870.

* Update apis.mustache

* added new petstore code.

modules/openapi-generator/src/main/resources/typescript-fetch/apis.mustache

@@ -232,7 +232,7 @@ export class {{classname}} extends runtime.BaseAPI {
         return new runtime.JSONApiResponse<any>(response);
         {{/isListContainer}}
         {{#returnSimpleType}}
-        return new runtime.TextApiResponse(response);
+        return new runtime.TextApiResponse(response) as any;
         {{/returnSimpleType}}
         {{/returnTypeIsPrimitive}}
         {{^returnTypeIsPrimitive}}

samples/client/petstore/typescript-fetch/builds/default/src/apis/UserApi.ts

@@ -244,7 +244,7 @@ export class UserApi extends runtime.BaseAPI {
             query: queryParameters,
         });
 
-        return new runtime.TextApiResponse(response);
+        return new runtime.TextApiResponse(response) as any;
     }
 
     /**

samples/client/petstore/typescript-fetch/builds/es6-target/src/apis/UserApi.ts

@@ -244,7 +244,7 @@ export class UserApi extends runtime.BaseAPI {
             query: queryParameters,
         });
 
-        return new runtime.TextApiResponse(response);
+        return new runtime.TextApiResponse(response) as any;
     }
 
     /**

samples/client/petstore/typescript-fetch/builds/multiple-parameters/src/apis/UserApi.ts

@@ -244,7 +244,7 @@ export class UserApi extends runtime.BaseAPI {
             query: queryParameters,
         });
 
-        return new runtime.TextApiResponse(response);
+        return new runtime.TextApiResponse(response) as any;
     }
 
     /**

samples/client/petstore/typescript-fetch/builds/prefix-parameter-interfaces/src/apis/UserApi.ts

@@ -244,7 +244,7 @@ export class UserApi extends runtime.BaseAPI {
             query: queryParameters,
         });
 
-        return new runtime.TextApiResponse(response);
+        return new runtime.TextApiResponse(response) as any;
     }
 
     /**

samples/client/petstore/typescript-fetch/builds/typescript-three-plus/src/apis/UserApi.ts

@@ -244,7 +244,7 @@ export class UserApi extends runtime.BaseAPI {
             query: queryParameters,
         });
 
-        return new runtime.TextApiResponse(response);
+        return new runtime.TextApiResponse(response) as any;
     }
 
     /**

samples/client/petstore/typescript-fetch/builds/with-interfaces/src/apis/UserApi.ts

@@ -244,7 +244,7 @@ export class UserApi extends runtime.BaseAPI {
             query: queryParameters,
         });
 
-        return new runtime.TextApiResponse(response);
+        return new runtime.TextApiResponse(response) as any;
     }
 
     /**

samples/client/petstore/typescript-fetch/builds/with-npm-version/src/apis/UserApi.ts

@@ -244,7 +244,7 @@ export class UserApi extends runtime.BaseAPI {
             query: queryParameters,
         });
 
-        return new runtime.TextApiResponse(response);
+        return new runtime.TextApiResponse(response) as any;
     }
 
     /**