Update Gradle Wrapper from 6.7 to 7.6

[github-actions]

Update Gradle Wrapper from 6.7 to 7.6.

Read the release notes: https://docs.gradle.org/7.6/release-notes.html

---

The checksums of the Wrapper JAR and the distribution binary have been successfully verified.

• Gradle release: 7.6
• Distribution (-all) zip checksum: 312eb12875e1747e05c2f81a4789902d7e4ec5defbd1eefeaccc08acf096505d
• Wrapper JAR Checksum: c5a643cf80162e665cc228f7b16f343fef868e47d3a4836f62e18b7e17ac018a

You can find the reference checksum values at https://gradle.org/release-checksums/

---

🤖 This PR has been created by the Update Gradle Wrapper action.

Need help? 🤔

If something doesn't look right with this PR please file an issue here.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}