Typo fix for dev guide README (openservicemesh#4347)

* Typo fix

Signed-off-by: Bridget Kromhout <bridget@kromhout.org>

* Update docs/development_guide/README.md

Co-authored-by: Jon Huhn <nojnhuh@users.noreply.github.com>
Signed-off-by: Jon Huhn <johuhn@microsoft.com>

Co-authored-by: Delyan Raychev <delyan.raychev@microsoft.com>
Co-authored-by: Jon Huhn <nojnhuh@users.noreply.github.com>

docs/development_guide/README.md

@@ -166,7 +166,7 @@ and each change would be accompanied by a unit test.
 To run all unit tests you can use the following `Makefile` target:
 
 ```bash
-make go-tests
+make go-test-coverage
 ```
 
 You can run the tests exclusively for the package you are working on. For example the following command will