Tool does not adhere to standards checked by M2 test runner

Nobody has claimed this yet.

When I run the Magento 2 tests, the migration tool gets flagged for hundreds of small issues.

```
# Run the full test runner with this
bin/magento dev:tests:run
# But I personally run one at a time since there are problems with the integration tests
bin/magento dev:tests:run static
```

Here are examples of the 2 main issues, but there are several instances of each of them:

- The XML file at /Users/me/Projects/m2.com/www/vendor/magento/data-migration-tool/tests/integration/testsuite/Migration/_files/map-tier-price.xml does not have a schema properly defined. It should have a xsi:noNamespaceSchemaLocation attribute defined with a URN path. E.g. xsi:noNamespaceSchemaLocation="urn:magento:framework:Relative_Path/something.xsd"
- Incorrect namespace usage(s) found in file /Users/me/Projects/m2.com/www/vendor/magento/data-migration-tool/tests/unit/testsuite/Migration/Step/Eav/HelperTest.php:

This does not affect our ability to use the migration tool, but it significantly impedes our usage of the static test runner--it is quite difficult to see our own issues that require fixes.

Run `bin/magento dev:tests:run static` and review the reported findings, starting with `tests/integration/testsuite/Migration/_files/map-tier-price.xml` and `tests/unit/testsuite/Migration/Step/Eav/HelperTest.php`. Compare the XML schema declarations and namespace usage with the standards reported by the runner. Done means the migration tool's static test run no longer reports these classes of issues.

Written by the indexing model from the issue text.