Validate the new semantic highlighter for TS

[aeschli]

Validate and enable the new semantic highlighter for TS

[aeschli]

Fixed by c09b3d2

[aeschli]

@mjbvz FYI

I tested the TS implementation against the existing tests in https://github.com/aeschli/typescript-vscode-sh-plugin

typescript-vscode-sh-plugin will no longer intercept for TS >= 4.2 (but will stick around a while to support older versions)