docs: document usage of middlewareModule with Magento 2 integration

[WojtekTheWebDev]

🔗 Linked issue

❓ Type of change

• [x] 📖 Documentation (updates to the documentation, readme or JSDoc annotations)
• [ ] 🐞 Bug fix (a non-breaking change that fixes an issue)
• [ ] 👌 Enhancement (improving an existing functionality like performance)
• [ ] ✨ New feature (a non-breaking change that adds functionality)
• [ ] 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• [ ] ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

Document usage of middlewareModule with Magento 2 integration

📝 Checklist

• [x] I have linked an issue or discussion.
• [x] I have updated the documentation accordingly.

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: e46e482c3f6447e2a01c618d14a8343d3ffc701e

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