Disable KotlinPropertyResolverExtensionsTests for now

Those tests produce intermittent build errors.

Author: sdeleuze

spring-core/src/test/kotlin/org/springframework/core/env/KotlinPropertyResolverExtensionsTests.kt

@@ -19,13 +19,15 @@ package org.springframework.core.env
 import io.mockk.every
 import io.mockk.mockk
 import io.mockk.verify
+import org.junit.jupiter.api.Disabled
 import org.junit.jupiter.api.Test
 
 /**
  * Mock object based tests for PropertyResolver Kotlin extensions.
  *
  * @author Sebastien Deleuze
  */
+@Disabled
 class KotlinPropertyResolverExtensionsTests {
 
 	val propertyResolver = mockk<PropertyResolver>()