Update Documentation for Policy Store and Policy Validation

[ds-jhartmann]

As system user or administrator, I want the documentation to be updated, so that the functionality of the Policy Store and Policy Validation is clearly described, providing detailed instructions on how to configure policies and explaining the consequences of these configurations.

Link

• relates to https://github.com/eclipse-tractusx/item-relationship-service/issues/361

Hints / Details

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Acceptance Criteria

• [ ] Describe how multiple policies can be configured and how they are validated
• [ ] Explain the case, where multiple acceptable offers are found

Out of Scope

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