update version in readme to 0.9.0

Author: Jolanrensen

README.md

@@ -1,7 +1,7 @@
 # Kotlin Dataframe: typesafe in-memory structured data processing for JVM
 [![JetBrains incubator project](https://jb.gg/badges/incubator.svg)](https://confluence.jetbrains.com/display/ALL/JetBrains+on+GitHub)
 [![Kotlin component alpha stability](https://img.shields.io/badge/project-alpha-kotlin.svg?colorA=555555&colorB=DB3683&label=&logo=kotlin&logoColor=ffffff&logoWidth=10)](https://kotlinlang.org/docs/components-stability.html)
-[![Kotlin](https://img.shields.io/badge/kotlin-1.7.20-blue.svg?logo=kotlin)](http://kotlinlang.org)
+[![Kotlin](https://img.shields.io/badge/kotlin-1.8.0-blue.svg?logo=kotlin)](http://kotlinlang.org)
 [![Maven Central](https://img.shields.io/maven-central/v/org.jetbrains.kotlinx/dataframe?color=blue&label=Maven%20Central)](https://search.maven.org/artifact/org.jetbrains.kotlinx/dataframe)
 [![GitHub License](https://img.shields.io/badge/license-Apache%20License%202.0-blue.svg?style=flat)](http://www.apache.org/licenses/LICENSE-2.0)
 
@@ -29,7 +29,7 @@ repositories {
     mavenCentral()
 }
 dependencies {
-    implementation 'org.jetbrains.kotlinx:dataframe:0.8.1'
+    implementation 'org.jetbrains.kotlinx:dataframe:0.9.0'
 }
 ```
 ### Jupyter Notebook