Update README.md

Remove `go htmlunit`, since htmlunit-driver is now in a separate project.

Signed-off-by: Alex Rodionov <[email protected]>

Author: asashour

README.md

@@ -168,7 +168,6 @@ want to build a single driver, then you can run one of these targets:
 ```sh
 ./go chrome
 ./go firefox
-./go htmlunit
 ./go ie
 ```