[TypeScript Fetch] Fix typo {{classname}}FetchParamCreactor

[albertpastrana]

PR checklist

• Read the contribution guildelines.
• Ran the shell/batch script under ./bin/ to update Petstore sample so that CIs can verify the change. (For instance, only need to run ./bin/{LANG}-petstore.sh and ./bin/security/{LANG}-petstore.sh if updating the {LANG} (e.g. php, ruby, python, etc) code generator or {LANG} client's mustache templates)
• Filed the PR against the correct branch: master for non-breaking changes and 2.3.0 branch for breaking (non-backward compatible) changes.

Description of the PR

There was a typo, this is just about changing FetchParamCreactor to FetchParamCreator.

I've done it in the 2.3.0 branch as this is potentially a breaking change (people out there using the class XFetchParamCreactor will need to modify their code).

[wing328]

@albertpastrana thanks for the PR.

Please resubmit it for 2.3.0 branch instead as you've pointed out it's a breaking change.

Please also run ./bin/typescript-fetch-petstore-all.sh to update the samples so that the CI can test the change.

[albertpastrana]

Sorry, I had two branches and it looks like I've ended up raising the PR against the wrong branch :(
Will close that one and submit it again.