package/ci: nope, this was not a good idea.

Test failures were silently ignored when done like this.

package/ci/appveyor-desktop-gles.bat

@@ -80,11 +80,13 @@ python setup.py install --root="%APPVEYOR_BUILD_FOLDER%/install" || exit /b
 
 rem Run tests & gather coverage
 cd ../../../src/python/corrade || exit /b
-coverage run -m unittest -v && cp .coverage ../.coverage.corrade || exit /b
+coverage run -m unittest -v || exit /b
+cp .coverage ../.coverage.corrade || exit /b
 
 cd ../magnum || exit /b
 set MAGNUM_SKIP_GL_TESTS=ON
-coverage run -m unittest -v && cp .coverage ../.coverage.magnum || exit /b
+coverage run -m unittest -v || exit /b
+cp .coverage ../.coverage.magnum || exit /b
 
 rem Test docstring validity
 cd ../../../doc/python || exit /b

package/ci/appveyor-desktop.bat

@@ -81,11 +81,13 @@ python setup.py install --root="%APPVEYOR_BUILD_FOLDER%/install" || exit /b
 
 rem Run tests & gather coverage
 cd ../../../src/python/corrade || exit /b
-coverage run -m unittest -v && cp .coverage ../.coverage.corrade || exit /b
+coverage run -m unittest -v || exit /b
+cp .coverage ../.coverage.corrade || exit /b
 
 cd ../magnum || exit /b
 set MAGNUM_SKIP_GL_TESTS=ON
-coverage run -m unittest -v && cp .coverage ../.coverage.magnum || exit /b
+coverage run -m unittest -v || exit /b
+cp .coverage ../.coverage.magnum || exit /b
 
 rem Test docstring validity
 cd ../../../doc/python || exit /b

package/ci/travis-desktop-gles.sh

@@ -70,10 +70,12 @@ python3 setup.py install --root="$TRAVIS_BUILD_DIR/install" --prefix=/usr
 
 # Run tests & gather coverage
 cd ../../../src/python/corrade
-coverage run -m unittest -v && cp .coverage ../.coverage.corrade
+coverage run -m unittest -v
+cp .coverage ../.coverage.corrade
 
 cd ../magnum
-coverage run -m unittest -v && cp .coverage ../.coverage.magnum
+coverage run -m unittest -v
+cp .coverage ../.coverage.magnum
 
 # Test docstring validity
 cd ../../../doc/python

package/ci/travis-desktop.sh

@@ -64,10 +64,12 @@ python3 setup.py install --root="$TRAVIS_BUILD_DIR/install" --prefix=/usr
 
 # Run tests & gather coverage
 cd ../../../src/python/corrade
-coverage run -m unittest -v && cp .coverage ../.coverage.corrade
+coverage run -m unittest -v
+cp .coverage ../.coverage.corrade
 
 cd ../magnum
-MAGNUM_SKIP_GL_TESTS=ON coverage run -m unittest -v && cp .coverage ../.coverage.magnum
+MAGNUM_SKIP_GL_TESTS=ON coverage run -m unittest -v
+cp .coverage ../.coverage.magnum
 
 # Test docstring validity
 cd ../../../doc/python