Update openapi-generator-version to v7.13.0 (line#551)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
|
[org.openapitools:openapi-generator-cli](https://redirect.github.com/openapitools/openapi-generator)
| `7.12.0` -> `7.13.0` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/org.openapitools:openapi-generator-cli/7.13.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/org.openapitools:openapi-generator-cli/7.13.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/org.openapitools:openapi-generator-cli/7.12.0/7.13.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/org.openapitools:openapi-generator-cli/7.12.0/7.13.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
|
[org.openapitools:openapi-generator](https://redirect.github.com/openapitools/openapi-generator)
| `7.12.0` -> `7.13.0` |
[![age](https://developer.mend.io/api/mc/badges/age/maven/org.openapitools:openapi-generator/7.13.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/maven/org.openapitools:openapi-generator/7.13.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/maven/org.openapitools:openapi-generator/7.12.0/7.13.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/org.openapitools:openapi-generator/7.12.0/7.13.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

<details>
<summary>openapitools/openapi-generator
(org.openapitools:openapi-generator-cli)</summary>

###
[`v7.13.0`](https://redirect.github.com/OpenAPITools/openapi-generator/releases/tag/v7.13.0):
released

[Compare
Source](https://redirect.github.com/openapitools/openapi-generator/compare/v7.12.0...v7.13.0)

v7.13.0 stable release comes with 160+ enhancements, bug fixes, and a
new [Kotlin Misk server
genreator](https://redirect.github.com/OpenAPITools/openapi-generator/pull/20885).

For a full list of changes, please refer to the ["Pull
Request"](https://redirect.github.com/OpenAPITools/openapi-generator/pulls?q=is%3Amerged+is%3Apr+milestone%3A7.13.0+)
tab.

</details>

---

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rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about these
updates again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

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generator/pom.xml

@@ -136,6 +136,6 @@
   </dependencies>
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <openapi-generator-version>7.12.0</openapi-generator-version>
+    <openapi-generator-version>7.13.0</openapi-generator-version>
   </properties>
 </project>