Use viewbox: true option when creating QR code in otp feature, displa…

…ys better and easier to style when using rqrcode 2+

The option is ignored in earlier versions, so no behavior change
there.  This makes the QR code slightly larger by default, but it
scales down better on smaller screen sizes.

CHANGELOG

@@ -1,5 +1,7 @@
 === master
 
+* Use viewbox: true option when creating QR code in otp feature, displays better and easier to style when using rqrcode 2+ (jeremyevans)
+
 * Make argon2 feature work with argon2 2.1.0+ (jeremyevans)
 
 === 2.17.0 (2021-09-24)

lib/rodauth/features/otp.rb

@@ -303,7 +303,7 @@ def otp_provisioning_name
     end
 
     def otp_qr_code
-      RQRCode::QRCode.new(otp_provisioning_uri).as_svg(:module_size=>8)
+      RQRCode::QRCode.new(otp_provisioning_uri).as_svg(:module_size=>8, :viewbox=>true)
     end
 
     def otp_user_key