[Elixir] Fix generation issues and compilation warnings in Elixir generator

[ntodd]

This PR improves Elixir code generation by resolving several issues observed when generating using the Procore API spec:

1. Previous reserved words list was incomplete. Updated to use the reserved words list from the Elixir language documentation.
2. Reserved words were being prefixed with an underscore. In Elixir this indicates that the variable is not being used and when it is used it will emit a warning. This updates the renaming function to use a suffix to avoid these warnings.
3. In rare cases, Typespecs were generating invalid types with a double "t" (e.g. ".t().t"). This change normalizes the names to improve reliability of the typespec generation.

@mrmstn

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[mrmstn]

Hi @ntodd
Firstly, thank you very much for your contribution and effort on bringing the elixir openapi gen a bit more forward :)

Second, I'm not quite sure if the failing pipeline triggered an email for you, but it looks like you didn't update the sample (or may not committed them) according to the CI.

Other than that, your PR looks good to me except for the removal of the Pseudo-variables, which should be treated as reserved words as well. Thank you very much for your contribution and the effort you already put in :)!

[ntodd]

@mrmstn I re-added the psuedo-variables and added __struct__ as well. I tweaked escapeReservedWord to better handle reserved words starting with underscores.

I did not address _ as @valpackett suggested. It could be added, but I'm not sure where to draw the line on what should be handled by the default list and what should be addressed by fixing --name-mappings functionality.

[mrmstn]

Hi @ntodd,
Thanks for your response and the updated code. I highly appreciated it and second, please excuse my longer response time, there's currently a lot going on, but I try me best to get the review squeezed in somewhere :)!

I looked through the generated samples, and it looks like the changes handle the primitive types not correctly for the type spec definitions!

[mrmstn]

Hi @ntodd,

I've made some changes to your code to get this PR moving forward. In my opinion, everything should be correct, but it would be great if you could review my changes to ensure I haven't missed anything.

If the changes look good to you, let's go ahead and merge this. If I don't hear back from you, I'll assume the changes are fine and plan to merge them by Tuesday.

The changes will be included in release 7.7.0. Alternatively, if you prefer to use the latest features, you can access them in the latest Docker container after the merge.

Thanks again for your time and effort! Your contributions are highly appreciated!

[ntodd]

@mrmstn Thanks for catching what I missed. Looks good to me!