Nodejs12 not supported in supportedRuntimes

[haolei]

Describe the bug Aliyun already has Nodejs12 runtime, but the extension source still not support Nodejs12 in supportedRuntimes. please fix this.

To Reproduce Steps to reproduce the behavior:

1. Go to 'Function Definition'
2. Click on 'create new function'
3. Input function name, and press enter
4. In pick runtime, nodejs12 is not in list.

Expected behavior nodejs12 should in runtime list

Screenshots If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: All OS
• VSCode Version: All version
• Aliyun Serverless Extension Version: All version

Additional context Add any other context about the problem here.