Updates kotest to 4.1.0 and moves it to property

Author: asm0dey

kotlin-spark-api/pom.xml

@@ -20,6 +20,7 @@
         <kotlin.version>1.3.72</kotlin.version>
         <kotlin.code.style>official</kotlin.code.style>
         <dokka.version>0.10.1</dokka.version>
+        <kotest.version>4.1.0</kotest.version>
     </properties>
 
     <dependencies>
@@ -46,13 +47,13 @@
         <dependency>
             <groupId>io.kotest</groupId>
             <artifactId>kotest-runner-junit5-jvm</artifactId>
-            <version>4.1.0</version>
+            <version>${kotest.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>io.kotest</groupId>
             <artifactId>kotest-assertions-core-jvm</artifactId>
-            <version>4.1.0</version>
+            <version>${kotest.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>