Adds unit tests for createAccountPage asyncActions

[supernova-at]

Description

Adds unit tests for createAccountPage/asyncActions.js.

Related Issue

Closes #886 .

Motivation and Context

Part of the ongoing effort to shore up unit test coverage in Venia.

How Has This Been Tested?

yarn test.

Screenshots (if appropriate):

Proposed Labels for Change Type/Package

TEST

venia-concept

Checklist:

• I have read the CONTRIBUTING document.
• I have linked an issue to this PR.
• I have indicated the change type and relevant package(s).
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• All CI checks are green (linting, build/deploy, etc).
• At least one core contributor has approved this PR.

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[coveralls]

Coverage decreased (-0.2%) to 61.977% when pulling 6f3d795 on supernova/886 into e4568a8 on release/2.0.

[coveralls]

Coverage increased (+0.09%) to 68.551% when pulling 42419de on supernova/886 into 548412e on release/2.0.