Unfortunately, Google doesn't make
armv7l) builds of ChroreDriver anymore. The latest version of
chromedriver-linux32 was released for version 2.33
But there is a solution, people from the Raspbian project have compiled chromium-chromedriver version for the
armhf platform and added it to the repo.
sudo apt-get install chromium-chromedriver
And you will have the latest available version of the ChromeDriver installed and ready to use together with Selenium.