Apply API Review feedback to JsonHubProtocolOptions

Specifically, we should review the JsonHubProtocolOptions for the new System.Text.Json based protocol.

[BrennanConroy]

Those are the defaults set by new JsonSerializerOptions(); I’m not setting 0 or 64. The ask is do we want to set these, or keep the defaults?

[BrennanConroy]

Acceptance checklist (check one item)

• We decided not to take this fix.
• The fix is tests-only.
• The fix contains product changes (check all items below).
  • Relevant XML documentation comments for new public APIs are present.
  • Narrative docs (docs.microsoft.com) are updated. (check one item below)
    • The change requires a new article. An issue with an outline has been filed here: [ISSUE LINK]
    • The change requires a change to an existing article. A closed docs PR with these changes is linked here: [PR LINK]
    • The change requires no docs changes.
  • Verification has been completed. (check one item below)
    • The change is in the shared framework and was verified against the following versions
      • SDK installer: [3.0.100-preview6-012096]
      • ASP.NET Core Runtime: [3.0.0-preview6-19277-03]
      • .NET Core Runtime: [3.0.0-preview6-27727-02]
    • The change is in an OOB NuGet/NPM/JAR package and was verified against the following version of that package: [PACKAGE ID] [VERSION]