Remove .vscode-test-web from extension package

[kidonng]

I noticed the extension takes surprisingly large disk space:

$ du -sh ~/.vscode/extensions/wakatime.vscode-wakatime-*/{,.}* | sort -h | tail -n3
796K	/Users/kid/.vscode/extensions/wakatime.vscode-wakatime-19.0.1/dist
 53M	/Users/kid/.vscode/extensions/wakatime.vscode-wakatime-19.0.0/.vscode-test-web
 54M	total

It seems like .vscode-test-web is a dependency only used in development:

$ rg vscode-test-web ~/.vscode/extensions/wakatime.vscode-wakatime-*
/Users/kid/.vscode/extensions/wakatime.vscode-wakatime-19.0.0/package.json
53:		"open-in-browser": "vscode-test-web --open-devtools --version sources --extensionDevelopmentPath=. .",

Having it in the final package doesn't make sense. I suggest removing it from the package before publishing to the marketplace.