[autotests] Specify XCUROSR_THEME and XCURSOR_SIZE in pointer input test

Try to fix test on CI system. With neither a config nor the env variables
the cursor selection falls back to the default cursor theme, which might
not contain the cursors we need.

autotests/wayland/pointer_input.cpp

@@ -96,6 +96,9 @@ void PointerInputTest::initTestCase()
 
     kwinApp()->setConfig(KSharedConfig::openConfig(QString(), KConfig::SimpleConfig));
 
+    qputenv("XCURSOR_THEME", QByteArrayLiteral("breeze_cursors"));
+    qputenv("XCURSOR_SIZE", QByteArrayLiteral("32"));
+
     kwinApp()->start();
     QVERIFY(workspaceCreatedSpy.wait());
     QCOMPARE(screens()->count(), 2);