fix typo

4-Containerized_Development_With_Volumes/README.md

@@ -43,7 +43,7 @@ Text that looks `like this --for --example` are commands that you should type in
 
 - [ ] Spin up a new container based on the 'colorserver' image you just built, mapping it to port 8080 on the host. Run `docker run -d -p 8080:8080 colorserver`
 
-- [ ] Open up your browser and visit `locahost:8080`. Notice that the color of the web page is 'SteelBlue'.
+- [ ] Open up your browser and visit `localhost:8080`. Notice that the color of the web page is 'SteelBlue'.
 
 - [ ] Now, pretend you are in a development environment and want to quickly test out several different colors to see which one looks best. Open up 'index.js' and change the color on line 12 from `'SteelBlue'` to the string `'SpringGreen'`