fix(completion): add TextEdit for fix #79

[yoyo930021]

• [x] Use TextEdit to fix #79, because LSP spec write this:

The `insertText` is subject to interpretation by the client side.
Some tools might not take the string literally. For example
VS Code when code complete is requested in this example `con<cursor position>`
and a completion item with an `insertText` of `console` is provided itwill only insert `sole`. Therefore it is recommended to use `textEdit` instead
since it avoids additional client side interpretation.

• [x] Add trace server option

[mergify[bot]]

This pull request is now in conflicts. Could you fix it?

[mrmlnc]

Sorry for trigger from the bot.

I'll try to get back to this PR later. Looks like the original issue is https://github.com/mrmlnc/vscode-scss/issues/79#issuecomment-589976014.

[yoyo930021]

I have the same problem when Vue file for only two vscode extensions. But this solution is too naive, I will update after having time.

[yoyo930021]

@mrmlnc I updated this PR.