Add localization to settings tab (#8012)

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## Summary of the Pull Request
Fixes the last bit of missing localization for the settings UI

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## References

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## PR Checklist
* [ ] Closes #xxx
* [ ] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [ ] Tests added/passed
* [ ] Documentation updated. If checked, please file a pull request on [our docs repo](https://github.com/MicrosoftDocs/terminal) and link it here: #xxx
* [ ] Schema updated.
* [ ] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx

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## Detailed Description of the Pull Request / Additional comments

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## Validation Steps Performed

src/cascadia/TerminalApp/Resources/en-US/Resources.resw

@@ -469,4 +469,7 @@
   <data name="CouldNotOpenUriDialog.PrimaryButtonText" xml:space="preserve">
     <value>Cancel</value>
   </data>
+  <data name="SettingsTab" xml:space="preserve">
+    <value>Settings</value>
+  </data>
 </root>

src/cascadia/TerminalApp/SettingsTab.cpp

@@ -40,6 +40,7 @@ namespace winrt::TerminalApp::implementation
     void SettingsTab::_MakeTabViewItem()
     {
         TabViewItem(::winrt::MUX::Controls::TabViewItem{});
+        Title(RS_(L"SettingsTab"));
         TabViewItem().Header(winrt::box_value(Title()));
     }
 

src/cascadia/TerminalApp/SettingsTab.h

@@ -36,7 +36,7 @@ namespace winrt::TerminalApp::implementation
         WINRT_CALLBACK(Closed, winrt::Windows::Foundation::EventHandler<winrt::Windows::Foundation::IInspectable>);
         WINRT_CALLBACK(PropertyChanged, Windows::UI::Xaml::Data::PropertyChangedEventHandler);
 
-        GETSET_PROPERTY(winrt::hstring, Title, L"Settings");
+        GETSET_PROPERTY(winrt::hstring, Title);
         GETSET_PROPERTY(winrt::hstring, Icon);
         GETSET_PROPERTY(winrt::Microsoft::Terminal::Settings::Model::Command, SwitchToTabCommand, nullptr);
         GETSET_PROPERTY(winrt::Microsoft::UI::Xaml::Controls::TabViewItem, TabViewItem, nullptr);