Fix KT-13021, KT-13020, Test for already fixed KT-6941

Fixes on javadoc to kdoc comments convert

j2k/testData/fileOrElement/docComments/aWithoutHref.java

@@ -0,0 +1,7 @@
+/**
+ * <a name="some_important_name">Important</a>
+ * <a>Just an link without href</a>
+ */
+public class A {
+
+}

j2k/testData/fileOrElement/docComments/aWithoutHref.kt

@@ -0,0 +1,5 @@
+/**
+ * <a name="some_important_name">Important</a>
+ * <a>Just an link without href</a>
+ */
+class A

j2k/testData/fileOrElement/docComments/escapedCharactersInCodeQuote.java

@@ -0,0 +1,5 @@
+/**
+ * {@code A<B}
+ */
+public class C {
+}

j2k/testData/fileOrElement/docComments/escapedCharactersInCodeQuote.kt

@@ -0,0 +1,4 @@
+/**
+ * `A<B`
+ */
+class C

j2k/testData/fileOrElement/docComments/preserveUnknownTags.java

@@ -0,0 +1,9 @@
+/**
+ * Doc comment.<p>
+ * <cite>cited</cite> <p>
+ * <span class="important_class">spanned</span> <p>
+ * <someSpecialTag>!!!</someSpecialTag>
+ */
+public class A {
+
+}

j2k/testData/fileOrElement/docComments/preserveUnknownTags.kt

@@ -0,0 +1,13 @@
+/**
+ * Doc comment.
+ *
+ *
+ * <cite>cited</cite>
+ *
+ *
+ * <span class="important_class">spanned</span>
+ *
+ *
+ * <someSpecialTag>!!!</someSpecialTag>
+ */
+class A