Extension causes high cpu load

[AnwerShujaFarooqui]

• Issue Type: Performance
• Extension Name: html-css-class-completion
• Extension Version: 1.18.0
• OS Version: Linux x64 4.15.0-48-generic
• VSCode version: 1.33.1

⚠️ Make sure to attach this file from your home-directory:
⚠️/home/anwer/Zignd.html-css-class-completion-unresponsive.cpuprofile.txt

Find more details here: https://github.com/Microsoft/vscode/wiki/Explain:-extension-causes-high-cpu-load

[zignd]

Duplicate of #155. Also, it is missing the file you were expected to attach.