fix(windows): "Keyboard" should be lower case in UI string for font helper tool

[rc-swag]

OS font helper UI string had a capital for K it should have been lower case k.

@keymanapp-test-bot skip

[keymanapp-test-bot[bot]]

User Test Results

Test specification and instructions

User tests are not required

Test Artifacts

• Windows
  • Keyman for Windows
  • FirstVoices Keyboards for Windows
  • Text Editor (32 bit)
  • Text Editor (64 bit)

[keyman-server]

Changes in this pull request will be available for download in Keyman version 18.0.31-alpha