MAGECLOUD-4264: Deliver patches for MSI

[shiftedreality]

Description

Backport of 2 issues:

Issue 1

• Eliminate group concat from source item indexer inventory#2515

Issue 2

• MSI-2210: Price Indexer fails with large catalogs inventory#2336
• Avoid querying inventory default stock view in storefront operations inventory#2350

Fixed Issues (if relevant)

1. https://magento2.atlassian.net/browse/MAGECLOUD-4264

Manual testing scenarios

magento/inventory#2336

• https://app.hiptest.com/projects/69435/test-plan/folders/908874/scenarios/3334423
• Price Indexer fails with large catalogs inventory#2210
• https://jira.corp.magento.com/browse/MC-15462

magento/inventory#2350

There is no test case targeting exactly this, as this is a purely performance improvement. Technically the system must behave absolutely similarly.
To make sure everything works we have gone through basic test cases on catalog browsing scenarios with installed MSI on default source and stock

• https://app.hiptest.com/projects/69435/test-plan/folders/908790/scenarios/1408726
• https://app.hiptest.com/projects/69435/test-plan/folders/911989/scenarios/1436612
• https://app.hiptest.com/projects/69435/test-plan/folders/457025/scenarios/1427936

If there is a technical ability it makes sense to check, that there are no excessive queries to inventory_stock_1 table when executing scenarios above

magento/inventory#2515

We do not have a 100% reproducible case for this scenario. It’s expected to fix inventory indexation in the case when most of the products in the system have excessively long SKUs
Scenarios above (for 2350) should work just fine to make sure that indexation is not broken by the change

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)

[shiftedreality]

@akaplya @ishakhsuvarov please have a look at version constraints

[andriyShevtsov]

@akaplya @ishakhsuvarov please review

[andriyShevtsov]

QA approved

[ghost]

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