Fix properties in deploy schema that require oneOf

[kfrancois]

Use oneOf instead of "type": ["a", "b"] to fix the ng deploy command.

Currently, running ng deploy with the @angular/fire:deploy builder results in the following error:

Property 'ssr' does not match the schema.
{
  "type": [
    "boolean",
    "string"
  ],
  "description": "Should we attempt to deploy the function to Cloud Functions (true or 'cloud-functions') / Cloud Run ('cloud-run') or just Hosting (false)"
}'

Running the same command with the proposed changes results in a successful deploy.

Checklist

• Issue number for this PR: SSR builder fails to deploy: generated configuration doesn't match the schema #3074
• Docs included?: no
• Test units included?: no
• In a clean directory, yarn install, yarn test run successfully? yes

Description

Code sample

[jamesdaniels]

Thanks for the fix!