Rename task unit-test to test:unit

Author: Nicoretti

doc/user_guide/getting_started.rst

@@ -77,7 +77,7 @@ Execute the unit tests of the project:
 
 .. code-block:: shell
 
-    nox -s unit-tests
+    nox -s test:unit
 
 
 .. _existing:

exasol/toolbox/nox/_test.py

@@ -72,7 +72,7 @@ def _coverage(
     session.run(*command)
 
 
-@nox.session(name="unit-tests", python=False)
+@nox.session(name="test:unit", python=False)
 def unit_tests(session: Session) -> None:
     """Runs all unit tests"""
     context = _context(session, coverage=False)