Fix writing kernelspec
Fix writing kernelspec

For #130602

I think we need to write it into metadata section instead of the top level

Microsoft/vscode,microsoft/vscode,eamodio/vscode,eamodio/vscode,Microsoft/vscode,microsoft/vscode,eamodio/vscode,Microsoft/vscode,microsoft/vscode,Microsoft/vscode,Microsoft/vscode,Microsoft/vscode,Microsoft/vscode,eamodio/vscode,eamodio/vscode,eamodio/vscode,eamodio/vscode,eamodio/vscode,microsoft/vscode,Microsoft/vscode,microsoft/vscode,microsoft/vscode,eamodio/vscode,Microsoft/vscode,microsoft/vscode,microsoft/vscode,microsoft/vscode,Microsoft/vscode,microsoft/vscode,eamodio/vscode,Microsoft/vscode,eamodio/vscode,microsoft/vscode,eamodio/vscode,eamodio/vscode,Microsoft/vscode,eamodio/vscode,microsoft/vscode,microsoft/vscode,microsoft/vscode,Microsoft/vscode,Microsoft/vscode,microsoft/vscode,Microsoft/vscode,Microsoft/vscode,microsoft/vscode,Microsoft/vscode,eamodio/vscode,microsoft/vscode,eamodio/vscode,eamodio/vscode