Replace process.exit with an else block

[erickoledadevrel]

Fixes #566

• [X ] npm test succeeds
• [ X] Pull request has been squashed into 1 commit
• [ X] I did NOT manually make changes to anything in apis/
• [ X] Code coverage does not decrease (if any source code was changed)
• [ X] Appropriate JSDoc comments were updated in source code (if applicable)
• [ X] Approprate changes to readme/docs are included in PR

The process.exit replaced a returnthat was failing a lint check, but ended up causing the generator to quit before the generation was complete.

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