Fixed for console error in checkout

[anatoliidolia]

Related Issues

Closes #556

Short Description and Why It's Useful

Only registered users have billing data;
Here added check for user registration;

Screenshots of Visual Changes before/after (If There Are Any)

Before (for the guest) :

After (for the guest) :

Contribution and Currently Important Rules Acceptance

• I read and followed contribution rules

[AishwaryShrivastav]

Changes in the PR looks good.

[AishwaryShrivastav]

@Fifciu, In case @anatoliidolia is busy and can't update the change log, I can update them, and we can merge these also, they are good to have changes for next release.

[anatoliidolia]

Hi @AishwaryShrivastav, how can I update them?

[AishwaryShrivastav]

@anatoliidolia in your branch, take pull of the develop, and move your change log entry to [1.0.5]

For reference: https://github.com/vuestorefront/vsf-capybara/pull/590/files

Thanks :)