fix translate arguments

[jdorr]

In this pull request, I update the logic in translate() to allow optional arguments.

I decided to open this pull request after I ran into a ui file compilation difference:

pyside2-uic foo.ui --> QCoreApplication.translate("MainWindow", u"MainWindow", None) (pyside-5.15.4)
pyside2-uic foo.ui --> QCoreApplication.translate("MainWindow", u"MainWindow", None, -1) (pyside-5.12.6)

Notice how the first compilation with pyside-5.15.4 returns translate with 3 arguments instead of 4. When we eventually use QtCompat.translate() we run into the following error:

  File "/dd/shows/DEV01/user/work.akelada/tools/cent7_64/package/launchpad/0.1.2/python/launchpad/Ui_launchpad_UI.py", line 205, in retranslateUi
    MainWindow.setWindowTitle(QtCompat.translate("MainWindow", u"MainWindow", None))
  File "/dd/tools/cent7_64/package/qt_py/1.3.6/python/Qt.py", line 844, in _translate
    "Expected 4 or 5 arguments, got {0}.".format(len(args) + 2))
TypeError: Expected 4 or 5 arguments, got 3.

Now translate("MainWindow", u"MainWindow", None) will work since n defaults to -1.

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[mottosso]

Almost got it haha.

Here's what I would do.

1. On GitHub.com
2. Make a new branch
3. Open Qt.py in the browser editor here on GitHub
4. Copy/paste your local Qt.py source code into the Qt.py in your webbrowser editor
5. Commit

Now you know the user who committed the code and the user making the PR are one and the same.