Revert "Merge pull request #3256 from thejeff77/feat/kotlin-nullable-schema-properties"

This reverts commit 6462e32, reversing
changes made to f634f54.

Author: thejeff77

springdoc-openapi-starter-common/src/main/java/org/springdoc/core/configuration/SpringDocKotlinConfiguration.kt

@@ -28,7 +28,6 @@ package org.springdoc.core.configuration
 
 import org.springdoc.core.converters.KotlinInlineClassUnwrappingConverter
 import org.springdoc.core.customizers.KotlinDeprecatedPropertyCustomizer
-import org.springdoc.core.customizers.KotlinNullablePropertyCustomizer
 import org.springdoc.core.providers.ObjectMapperProvider
 import org.springdoc.core.utils.Constants
 import org.springdoc.core.utils.SpringDocKotlinUtils
@@ -78,13 +77,6 @@ class SpringDocKotlinConfiguration() {
 			return KotlinDeprecatedPropertyCustomizer(objectMapperProvider)
 		}
 
-		@Bean
-		@Lazy(false)
-		@ConditionalOnMissingBean
-		fun kotlinNullablePropertyCustomizer(objectMapperProvider: ObjectMapperProvider): KotlinNullablePropertyCustomizer {
-			return KotlinNullablePropertyCustomizer(objectMapperProvider)
-		}
-
 		@Bean
 		@Lazy(false)
 		@ConditionalOnMissingBean