Clear control characters from expiry date string before parsing

[ddayguerrero]

Changes

Fixes a parsing bug with the expiry field when typing in a RTL context. Since we are currently using a u200e control character to override the directionality of the card number and expiry date fields, it causes our month variable in payform.parseCardExpiry to return NaN.

> const expiryString = '\u200e'.concat('12/21');
<- undefined
> const expiryValues = expiryString.split('/');
<- undefined
> expiryValues
<- (2) ["‎12", "21"]
> const month = parseInt(expiryValues[0], 10);
<- undefined
> month
<- NaN

Why introduce these changes?

• It is currently not possible to obtain the month variable when using the exposed payform.parseCardExpiry() function in a RTL context.

How is this achieved?

• Use the replace() function and a regex for \u200e to remove all its occurences from the string before it gets parsed.
• I double checked to make sure that this behaviour is not present with card numbers or the expiry year.