Fix enum rendering to use enum class in Kotlin signatures

dokka-subprojects/plugin-base/src/main/kotlin/org/jetbrains/dokka/base/signatures/KotlinSignatureProvider.kt

@@ -174,7 +174,7 @@ public class KotlinSignatureProvider(
                 }
                 is DEnum -> {
                     processExtraModifiers(c)
-                    keyword("enum ")
+                    keyword("enum class ")
                 }
                 is DObject -> {
                     processExtraModifiers(c)

dokka-subprojects/plugin-base/src/test/kotlin/signatures/SignatureTest.kt

@@ -628,15 +628,15 @@ class SignatureTest : BaseAbstractTest() {
     }
 
     @Test
-    fun `kotlin enum should render just enum`() = testRender(
+    fun `kotlin enum should render enum class`() = testRender(
         """
             |/src/main/kotlin/common/Test.kt
             |package example
             |enum class EnumClass { T }
         """.trimMargin()
     ) {
         renderedContent("root/example/-enum-class/index.html").firstSignature().matchIgnoringSpans(
-            "enum", A("EnumClass"), ":", A("Enum"), "<", A("EnumClass"), ">"
+            "enum class", A("EnumClass"), ":", A("Enum"), "<", A("EnumClass"), ">"
         )
     }
 
@@ -719,15 +719,15 @@ class SignatureTest : BaseAbstractTest() {
     }
 
     @Test
-    fun `java enum should render just enum`() = testRender(
+    fun `java enum should render enum class`() = testRender(
         """
             |/src/example/EnumClass.java
             |package example;
             |public enum EnumClass { T; }
         """.trimMargin()
     ) {
         renderedContent("root/example/-enum-class/index.html").firstSignature().matchIgnoringSpans(
-            "enum", A("EnumClass"),
+            "enum class", A("EnumClass"),
         )
     }