Describe the bug
I'm unable to add parenthesis and give parameters to a function using tab to go to the next parameter.

To Reproduce

1. Define a function that accepts one or more parameters.
2. Try to call the function by starting typing it's name and autocompleting it.
3. See that the only thing that is autocompleted is the name of the function.

Below is a recording of my screen that demonstrates the issue.

Expected behavior
Below is a recording of my screen while I autocomplete a simple console.log() statement. This is how the autocomplemetion on Dart code should've worked.

Insert Argument Placeholder option is enabled and enableCompletionCommitCharacters option is disabled.

Versions (please complete the following information):

• VS Code version: 1.49.2
• Dart extension version: 3.14.1
• Dart/Flutter SDK version: Dart - 2.9.2 / Flutter - 1.20.4