Fix test definition

Author: k163377

src/test/kotlin/com/fasterxml/jackson/module/kotlin/test/github/Github148.kt

@@ -1,6 +1,7 @@
 package com.fasterxml.jackson.module.kotlin.test.github
 
 import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper
+import org.junit.jupiter.api.Nested
 import org.junit.jupiter.api.Test
 import kotlin.test.assertEquals
 
@@ -32,7 +33,8 @@ class TestGithub148 {
         val type: IncorrectType
     )
 
-    class DemoApplicationTests {
+    @Nested
+    inner class DemoApplicationTests {
         val objectMapper = jacksonObjectMapper()
 
         @Test
@@ -45,4 +47,4 @@ class TestGithub148 {
             assertEquals("{\"name\":\"incorrent\",\"type\":\"TYPEA\"}", objectMapper.writeValueAsString(IncorrentBean("incorrent", IncorrectType.TYPEA)))
         }
     }
-}
+}