[Backport] ISSUE-5021 - fixed place order for custom shipping methods with under…

[gelanivishal]

Original PR

#18689

…score in carrier code

This fix allows to add custom shipping method with underscore in custom carrier code.

Description (*)

This fix avoid problem with incorrect shipping method code when logged in customer want to place order using custom shipping method with underscore in carrier code or method.
Issue was reproduced on versions:

• 2.1.9
• 2.2.5
• 2.3

Fixed Issues (if relevant)

1. "Please specify a shipping method" Exception #5021: "Please specify a shipping method" Exception

Manual testing scenarios (*)

1. Create custom shipping method module with underscore '_' in carrier code eg. "custom_shipping"
2. Enable custom shipping method
3. Create account and log in
4. Add product to cart
5. Go to checkout and select custom shipping method
6. Place order

Contribution checklist (*)

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)

[magento-engcom-team]

Hi @gelanivishal. Thank you for your contribution
Here is some useful tips how you can test your changes using Magento test environment.
Add the comment under your pull request to deploy test or vanilla Magento instance:

• @magento-engcom-team give me test instance - deploy test instance based on PR changes
• @magento-engcom-team give me $VERSION instance - deploy vanilla Magento instance

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[magento-engcom-team]

Hi @VladimirZaets, thank you for the review.
ENGCOM-3315 has been created to process this Pull Request

[magento-engcom-team]

Hi @gelanivishal. Thank you for your contribution.
We will aim to release these changes as part of 2.2.8.
Please check the release notes for final confirmation.

Please, consider to port this solution to 2.3 release line.
You may use Porting tool to port commits automatically.