Canary [regression] Trap when trying to use background image alignment that is not centered

[Zeroes1]

Windows Terminal version

1.23.10282.0

Windows build number

10.0.19045.3448

Other Software

No response

Steps to reproduce

1. Set use background image in default profile
2. Try use any alignment background image that is not centered
   for example in settings.json:
   "backgroundImageAlignment": "bottomRight",

after we got exception...

100% reproduced.

Windows create crashdump.

Expected Behavior

under Canary build:
..
terminal-1.23.10151.0 - latest good

Actual Behavior

terminal-1.23.10221.0 - with trouble
terminal-1.23.10271.0 - with trouble
terminal-1.23.10282.0 - with trouble

[Zeroes1]

ExceptionAddress: 00007ff9ddf0fc29 (Microsoft_Terminal_Settings_Editor!winrt::impl::consume_Windows_ApplicationModel_Resources_Core_IResourceCandidatewinrt::Windows::ApplicationModel::Resources::Core::IResourceCandidate::ValueAsString+0x000000000000002a)
ExceptionCode: c0000005 (Access violation)

STACK_TEXT:
Microsoft_Terminal_Settings_Editor!GetLibraryResourceString+0x159
Microsoft_Terminal_Settings_Editor!winrt::Microsoft::Terminal::Settings::Editor::implementation::AppearanceViewModel::BackgroundImageAlignmentCurrentValue+0x496
Microsoft_Terminal_Settings_Editor!winrt::impl::producewinrt::Microsoft::Terminal::Settings::Editor::implementation::AppearanceViewModel,winrt::Microsoft::Terminal::Settings::Editor::IAppearanceViewModel::get_BackgroundImageAlignmentCurrentValue+0x2a

[DHowett]

@carlos-zamora this is in the new SUI a11y previews

[DHowett]

@Zeroes1 Thank you so much for using Canary and filing these bugs on us. We are close to 1.23 release, so it is VERY HELPFUL!