add onBlur handler to compensate for no onChange after a paste

[dkackman]

Fix #315

MaskedInput is not raising onChange when a value that gets masked is pasted. Specically, if a value like " 1.0" is pasted this handler isn't being triggered.

uNmAnNeR/imaskjs#1063

onChange={(e) => {
  assets.cats[i].amount = e.target.value;
  setAssets({ ...assets });
}}

Since that is idempotent, adding an identical onBlur handler seems to work around this limitation.

Video showing repro steps. The value pasted is " 111.11", the leading non-numeric value is the trigger.

https://share.icloud.com/photos/0f5XhZUHCc7mOZ4uXJQdQn7eg

[dkackman]

closing this one in favor of #329