fix: Move reserved prop to App Service Plan

[tbarlow12]

What did you implement:

Small update to move reserved property from site resource to app service plan resource.

Closes #437

How did you implement it:

See above.

How can we verify it:

Deploy a premium node linux function app. It shouldn't fail

Todos:

Note: Run npm run test:ci to run all validation checks on proposed changes

• [x] Ensure there are no lint errors.
  Validate via npm run lint
  Note: Some reported issues can be automatically fixed by running npm run lint:fix
• [x] Write tests and confirm existing functionality is not broken.
  Validate via npm test
• [x] Write documentation
• [x] Provide verification config / commands / resources
• [x] Enable "Allow edits from maintainers" for this PR
• [x] Update the messages below

Is this ready for review?: YES Is it a breaking change?: NO

[grizzly-monkey]

ETA for this merge ? Excited to see this in action.

[tbarlow12]

@grizzly-monkey as soon as I can get an approval 👍 Working towards a v2 release soon

[pjlittle]

LGTM