Dashboard: add edit widget FOLIO keyboard shortcut

Stripes incorporates a set of keyboard shortcut keys for implementation across all apps. See:

• Section "Platform-wide keyboard shortcuts (each app must implement) " on the wiki page Key Navigation https://wiki.folio.org/display/A11Y/Keyboard+Navigation
• Keyboard commands API: https://github.com/folio-org/stripes-components/tree/master/lib/Commander

The following shortcuts should be implemented in Dashboard in addition to those identified in ERM-1735:

1. Edit selected widget (focus must be on any element on the widget) - cmd/ctrl + option/alt + e

Dev task breakdown

• Firstly implement existing patterns from ERM-1151, ERM-1239, ERM-1240, ERM-1241 
• Using this component, add a shortcut to open the modal.
• Existing shortcut code can be found by searching for HasCommand component
• No existing shortcut code in `defaultKeyboardShortcuts` for this, so append a new one for now  Check with Claudia who knows shortcuts code best atm