[Bug] Latest v1 library is leading to broken function definitions when using OAS tags with spaces

Hello! I tried updating to the latest version of this library, but ran into some errors since my OAS tags had spaces in them. I created a small fix PR with some tests to reproduce the issue: https://github.com/cyclosproject/ng-openapi-gen/pull/397

It seems to be an unintended regression from https://github.com/cyclosproject/ng-openapi-gen/commit/ee7f654