Fix Port Attributes constructor

[alexr00]

Fixes #183850

[alexr00]

When I updated the API to deprecate the old constructor, the bad type check broke the API for the Jupyter extension. It's safe to remove the old constructor entirely because all extensions that rely on the old constructor have moved off of it.
There are 2 current users of this API:

• ms-vscode.js-debug has never used this constructor: https://github.com/microsoft/vscode-js-debug/blob/63141a9d43e1fe38e3701b1f24d88ba670fd2c11/src/ui/portAttributesProvider.ts#L41
• ms-toolsai.jupyter has made the code change to move away from the old constructor already and will work as exepceted after publishing their next update: microsoft/vscode-jupyter@cd19546