fix(deps): update dependency io.projectreactor:reactor-core to v3.6.4

Author: renovate[bot]

OktaneCore/pom.xml

@@ -17,7 +17,7 @@
         <sonar.organization>k-boyle</sonar.organization>
         <sonar.host.url>https://sonarcloud.io</sonar.host.url>
 
-        <reactor-core.version>3.4.9</reactor-core.version>
+        <reactor-core.version>3.6.4</reactor-core.version>
 
         <auto-service-annotations.version>1.0</auto-service-annotations.version>
     </properties>