[Fix] forgot to add lowercase conversion on grouped product assignation

[jalogut]

Forgot to add lowercase conversion on grouped product assignation after changes done in MAGETWO-67240

• See changes done for MAGETWO-67240 here 02596b7#diff-b876c962d83b3bee42acba83af842309

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• Pull request has a meaningful description of its purpose
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• All new or changed code is covered with unit/integration tests (if applicable)
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[dmanners]

Hi @jalogut we have #12853 PR that was merged into 2.3. Could you please check as there is some extra changes in this from your PR. I wonder if we need a few more changes in your PR to complete this fix.

[magento-engcom-team]

Hi @jalogut. Thank you for your contribution.
Changes from your Pull Request will be available with the upcoming 2.2.5 release.

Please, consider porting this solution across release lines.
You may use Porting tool to port commits automatically.

[jalogut]

Sorry, what is this porting tool exactly for? Never done a port before and I do not really understand what it does. Could you maybe explain it with an example? Thanks.

[dmanners]

Hi @jalogut this tool has been created to allow you to take your pull request and port it to other versions of Magento. By using the url https://porting.engcom.dev.magento.com/, providing the right github information and supplying your pull request url it will attempt to create a PR to 2.1 and 2.3 from your pull request.