[TextExtractor] Minor UI/Accessibility fixes

[davidegiacometti]

Summary of the Pull Request

• Made narrator announce languages
• Made narrator announce the cancel button
• Changed languages list to show the first letter as upper case
• Fixed margin in order to center the buttons in the top bar

PR Checklist

• Closes: [Power Toys-System Tool >Text Extractor]: Name is not defined for the Cancel icon button on Power Toy Text Extractor. #36038 [Power Toys-System Tool >Text Extractor]: When navigating to the 'Select Language' combo box, the screen reader does not announce the currently selected language. #36039 TextExtractor: Russian starts with lowercase #32831
• Communication: I've discussed this with core contributors already. If work hasn't been agreed, this work might be rejected
• Tests: Added/updated and all pass
• Localization: All end user facing strings can be localized
• Dev docs: Added/updated
• New binaries: Added on the required places
  • JSON for signing for new binaries
  • WXS for installer for new binaries and localization folder
  • YML for CI pipeline for new test projects
  • YML for signed pipeline
• Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

0.86 - PR

Validation Steps Performed

Manually tested using Narrator