Remove buggy await tw.init(); call

[atihonovschi]

This is to resolve issue #802

• Removed call await tw.init() which led to improper initialization communication while LSP client does't support dynamic registration
• Removed unnecessary parameter connection and check for connection.onInitialized inside the supportsDynamicRegistration() method

[happysalada]

@bradlc sorry to ping you directly. This PR fixes an issue that prevents usage in the helix editor. Its not a major editor, but it would be amazing to have this merged.

[bradlc]

Hey @atgote, thanks for investigating the issue and opening this PR! I hope you don't mind I updated the PR slightly to avoid "unhandled method" errors.

Going to merge this, and then a new insiders version of @tailwindcss/language-server will automatically be published shortly afterwards (npm i @tailwindcss/language-server@insiders)

If you spot any other issues please let me know 👍