Add mockwebserver3

[koppor]

• https://github.com/square/okhttp/blob/master/mockwebserver/src/main/java9/module-info.java
• https://central.sonatype.com/artifact/com.squareup.okhttp3/mockwebserver3

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Makes following patch obsolete:

    module("com.squareup.okhttp3:mockwebserver3", "mockwebserver3") {
        patchRealModule()
        exportAllPackages()
        requireAllDefinedDependencies()
    }

[testlens-app]

✅ All tests passed ✅

🏷️ Commit: 52f7363
▶️ Tests: 186 executed
⚪️ Checks: 1/1 completed

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[koppor]

This refs JabRef/jabref#15876

[jjohannes]

Thanks @koppor