Added code to display error message from grapqhl response in form

[del22123]

Description

This PR contains the fix for customer login flow when require email confirmation is enabled.
Appropriate error message response from the graphql on customer creation will be shown in the form

This change requires few changes in Magento backend code.
Backend PR:
https://github.com/magento-commerce/magento2-pwa/pull/61

Closes #PWA-3367
https://jira.corp.adobe.com/browse/PWA-3367

Acceptance

Verification Stakeholders

Specification

Verification Steps

Step 1: Enable customer email confirmation from Magento Admin panel -> Stores -> Customer -> Customer Configuration -> Create New Account Options -> Require Emails Confirmation -> Yes and save the config
Step 2: In PWA store view add a product to cart and the go to Checkout page -> Sign In-> Create an account or Header -> Sign in -> Create an account
Step 3: Enter all the necessary details for the new customer account (Email should not exist already in the website)
Step 4: Click create an account button

Current result:
General error is thrown instead of more relevant error
(Error: An error has occurred. Please check the input and try again.)

Fix result:
Actual message from Magento graphql will be shown.
(Your account is created, You must confirm your account. Please check your email for the confirmation link.)

Screenshots / Screen Captures (if appropriate)

Breaking Changes (if any)

Checklist

• I have added tests to cover my changes, if necessary.
• I have added translations for new strings, if necessary.
• I have updated the documentation accordingly, if necessary.

[pwa-studio-bot]

	Fails
🚫	node failed.
🚫	GraphQL queries did not pass. Make sure to execute yarn run validate-queries locally prior to committing.
🚫	Unit tests in the following files did not pass 😔. All tests must pass before this PR can be merged packages/peregrine/lib/talons/FormError/__tests__/useFormError.spec.js

	Messages
📖	Associated JIRA tickets: PWA-3367.
📖	DangerCI Failures related to missing labels/description/linked issues/etc will persist until the next push or next pr-test build run (assuming they are fixed).
📖	Access a deployed version of this PR here. Make sure to wait for the "pwa-pull-request-deploy" job to complete.

Log

ERROR ON TASK: unitTests

ERROR ON TASK: validateQueries

Error:  Danger had errors running. See message(s) above for more details.
danger-results://tmp/danger-results.json

Generated by 🚫 dangerJS against 5963e11