Extension causes high cpu load

- Issue Type: `Performance`
- Extension Name: `vscode-basys`
- Extension Version: `0.2.3`
- OS Version: `Windows_NT x64 10.0.18362`
- VSCode version: `1.43.0`



[basys.vscode-basys-unresponsive.cpuprofile.txt](https://github.com/basys/vscode-basys/files/4328792/basys.vscode-basys-unresponsive.cpuprofile.txt)


