Making custom functions default to shared runtime

[igor-ribeiiro]

Thank you for your pull request. Please provide the following information.

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1. Do these changes impact User Experience? (e.g., how the user interacts with Yo Office and/or the files and folders the user sees in the project that Yo Office creates)

   • [X] Yes
   • [ ] No

Make CF project now use by default the shared runtime.

2. Do these changes impact documentation? (e.g., a tutorial on https://docs.microsoft.com/en-us/office/dev/add-ins/overview/office-add-ins)

   • [X] Yes
   • [ ] No

Will need to contact the documentation team to update their shared runtime tutorial, as it is not needed anymore.

3. Validation/testing performed:

Tested that when selecting this new option and downloading the template from the right place.

4. Platforms tested:

   • [X] Windows
   • [ ] Mac

[millerds]

Email suggests that we may not want one or the other, but rather both.