Upgrade maven wrapper to 3.9.9 (#830)

Here are some things you should have thought about:

**Multi-Tenancy**
- [ ] Extended new entities with `AbstractTenantAwareEntity`?
- [ ] New entity added to `TenantAwareDatabaseConfiguration`?
- [ ] Tested with `dev-multitenant` profile?

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.mvn/wrapper/maven-wrapper.properties

@@ -16,4 +16,4 @@
 # under the License.
 wrapperVersion=3.3.2
 distributionType=only-script
-distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.8/apache-maven-3.9.8-bin.zip
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.9/apache-maven-3.9.9-bin.zip