update main version (microsoft#16663)

Author: karthiknadig

package-lock.json

@@ -2,7 +2,7 @@
  "name": "python",
  "displayName": "Python",
  "description": "IntelliSense (Pylance), Linting, Debugging (multi-threaded, remote), Jupyter Notebooks, code formatting, refactoring, unit tests, and more.",
- "version": "2021.7.0-rc",
+ "version": "2021.8.0-dev",
  "featureFlags": {
  "usingNewInterpreterStorage": true
  },