[REF] tox: Build ChangeLog again (#466)

ChangeLog requires 'pbr'

But the tox build was installing requirements manually instead of installing the test-requirements.txt file were all them are considered

tox.ini

@@ -43,10 +43,7 @@ commands =
 [testenv:build]
 skip_install = true
 deps =
-    build
-    bump2version
-    twine
-    wheel
+    {[testenv]deps}
 commands =
     python -m build --sdist --wheel --outdir dist_wo_pbr/
     python -c "import shutil;shutil.rmtree('dist/', ignore_errors=True)"