NTR - fix es backend index

[teiling88]

1. Why is this change necessary?

Without this changes you cannot use it with elasticsearch 8

2. What does this change do, exactly?

3. Describe each step to reproduce the issue or behaviour.

4. Please link to the relevant issues (if any).

5. Which documentation changes (if any) need to be made because of this PR?

6. Checklist

• I have written tests and verified that they fail without my change
• I have squashed any insignificant commits
• This change has comments for package types, values, functions, and non-obvious lines of code
• I have read the contribution requirements and fulfil them.

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[mitelg]

hey @teiling88

thanks for you fix! Can we adjust our test pipeline, to make sure we stay compatible with ES8?

[teiling88]

At the moment, you are not compatible to es 8 with the es backend. So I don't get your question. I see no test for the es backend wich is testing the integration to es 8.

[mitelg]

there are a few 😬 https://github.com/shopware5/shopware/tree/5.7/tests/Functional/Bundle/EsBackendBundle

my idea was to change the ES version here https://github.com/shopware5/shopware/blob/5.7/.github/workflows/phpunit.yml#L161
I don't know, if this would be sufficient