Credentials fallback causing "Object is possibly 'undefined'" with strict-null-checks enabled

Created by: Chasoor

Hi, we love using the generator but the follwoing line is causing errors in our angular project (strict-null-checks enabled) since "apiKeys" is possibly undefined. Would be great if "apiKeys" had a null/undefined check with a default same as "credentials" or if the fallback is removed as suggested by the comment. Thank you in advance.

https://github.com/OpenAPITools/openapi-generator/blob/cc5e0fee2da407355266397e3e5d3fb3dc061cd6/modules/openapi-generator/src/main/resources/typescript-angular/configuration.mustache#L67