Update dependency org.openapi.generator to v7.20.0 (#904)

This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|
| org.openapi.generator | `7.19.0` → `7.20.0` |
![age](https://developer.mend.io/api/mc/badges/age/maven/org.openapi.generator:org.openapi.generator.gradle.plugin/7.20.0?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/org.openapi.generator:org.openapi.generator.gradle.plugin/7.19.0/7.20.0?slim=true)
|

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gradle/libs.versions.toml

@@ -42,7 +42,7 @@ workRuntimeKtx = "2.11.1"
 paletteKtx = "1.0.0"
 kotlinxCoroutinesTest = "1.10.2"
 coreTesting = "2.2.0"
-openapi-generator = "7.19.0"
+openapi-generator = "7.20.0"
 
 [libraries]
 aboutlibraries-core = { module = "com.mikepenz:aboutlibraries-core", version.ref = "aboutLibraries" }