Make the settings dialog as small as possible

Fixes: https://launchpad.net/bugs/1668669

openlp/core/ui/settingsdialog.py

@@ -39,7 +39,7 @@ class Ui_SettingsDialog(object):
         """
         settings_dialog.setObjectName('settings_dialog')
         settings_dialog.setWindowIcon(build_icon(u':/icon/openlp-logo.svg'))
-        settings_dialog.resize(800, 700)
+        settings_dialog.resize(920, 625)
         self.dialog_layout = QtWidgets.QGridLayout(settings_dialog)
         self.dialog_layout.setObjectName('dialog_layout')
         self.dialog_layout.setContentsMargins(8, 8, 8, 8)

tests/functional/openlp_core_ui/test_settingsform.py

@@ -151,3 +151,14 @@ class TestSettingsForm(TestCase):
         # THEN: The general tab's cancel() method should have been called, but not the themes tab
         mocked_general_cancel.assert_called_with()
         self.assertEqual(0, mocked_theme_cancel.call_count, 'The Themes tab\'s cancel() should not have been called')
+
+    def test_register_post_process(self):
+        # GIVEN: A settings form instance
+        settings_form = SettingsForm(None)
+        fake_function = MagicMock()
+
+        # WHEN: register_post_process() is called
+        settings_form.register_post_process(fake_function)
+
+        # THEN: The fake function should be in the settings form's list
+        assert fake_function in settings_form.processes