Bump kotlinx-coroutines.version from 1.6.4 to 1.8.1

Bumps `kotlinx-coroutines.version` from 1.6.4 to 1.8.1.

Updates `org.jetbrains.kotlinx:kotlinx-coroutines-jdk8` from 1.6.4 to 1.8.1
- [Release notes](https://github.com/Kotlin/kotlinx.coroutines/releases)
- [Changelog](https://github.com/Kotlin/kotlinx.coroutines/blob/master/CHANGES.md)
- [Commits](Kotlin/kotlinx.coroutines@1.6.4...1.8.1)

Updates `org.jetbrains.kotlinx:kotlinx-coroutines-reactor` from 1.6.4 to 1.8.1
- [Release notes](https://github.com/Kotlin/kotlinx.coroutines/releases)
- [Changelog](https://github.com/Kotlin/kotlinx.coroutines/blob/master/CHANGES.md)
- [Commits](Kotlin/kotlinx.coroutines@1.6.4...1.8.1)

Updates `org.jetbrains.kotlinx:kotlinx-coroutines-rx3` from 1.6.4 to 1.8.1
- [Release notes](https://github.com/Kotlin/kotlinx.coroutines/releases)
- [Changelog](https://github.com/Kotlin/kotlinx.coroutines/blob/master/CHANGES.md)
- [Commits](Kotlin/kotlinx.coroutines@1.6.4...1.8.1)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlinx:kotlinx-coroutines-jdk8
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.jetbrains.kotlinx:kotlinx-coroutines-reactor
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.jetbrains.kotlinx:kotlinx-coroutines-rx3
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

core-kotlin-modules/core-kotlin-concurrency-2/pom.xml

@@ -32,7 +32,7 @@
     </dependencies>
 
     <properties>
-        <kotlinx-coroutines.version>1.6.4</kotlinx-coroutines.version>
+        <kotlinx-coroutines.version>1.8.1</kotlinx-coroutines.version>
     </properties>
 
 </project>

kotlin-self-executable-jar/kotlin-spring-executable/pom.xml

@@ -48,7 +48,7 @@
         <dependency>
             <groupId>org.jetbrains.kotlinx</groupId>
             <artifactId>kotlinx-coroutines-reactor</artifactId>
-            <version>1.7.0</version>
+            <version>1.8.1</version>
         </dependency>
         <!-- Spring Boot Starter Test -->
         <dependency>