add the 'make test' command

Makefile

@@ -32,6 +32,13 @@ init:
 	borg init -e repokey-blake2; \
 	)
 
+test:
+	@. venv/bin/activate
+	@( \
+	cd tests/; \
+	python3 -m unittest; \
+	)
+
 clean: distclean
 	rm -rf build/
 	rm -rf venv/

README.org

@@ -88,11 +88,12 @@ pip3 install -r requirements.txt
 #+end_src
 
 You're now all set to work on Borg-Qt. It's a good idea to run the tests before
-starting. You can do this with the following command. Run from inside the
-~tests/~ directory.
+starting. You can do this with the following command from the root of the
+repository.
 
 #+begin_src sh
-python3 -m unittest
+make test
+#+end_src
 #+end_src
 
 ** Used packages