Improvements to overlay keybinds.

Added dynamic keybinder for overlays. If dismissable, the Escape key will dismiss the overlay. If not dismissable, Enter & Escape will trigger the main button.
If the selected account is not valid and you have more than one other account, you may cancel logging in to return to the original error overlay.
Updated electron-builder@20.28.2.
Fixed minor bug where the background of the settings UI was set to transparent. This occurred if the validation error overlay was shown on the settings UI, and you chose the login option.

app/assets/js/scripts/landing.js

@@ -145,10 +145,10 @@ function updateSelectedServer(serverName){
 }
 // Real text is set in uibinder.js on distributionIndexDone.
 updateSelectedServer('Loading..')
-server_selection_button.addEventListener('click', (e) => {
+server_selection_button.onclick = (e) => {
     e.target.blur()
     toggleServerSelection(true)
-})
+}
 
 // Update Mojang Status Color
 const refreshMojangStatuses = async function(){