ClassCastException in IndentationRule when blank line is added after @implNote tag in KDoc

[petertrr]

Describe the bug

class Foo {
    /**
     * @implNote lorem ipsum
     */
    private fun foo() {}
}

crashes diktat, but with one empty line (* ) after implNote - it doesn't. Problem is, most probably, in how KdocFormatting adds empty lines.

Observed behavior

Caused by: java.lang.ClassCastException: class org.jetbrains.kotlin.com.intellij.psi.impl.source.tree.LeafPsiElement cannot be cast to class org.jetbrains.kotlin.com.intellij.psi.PsiWhiteSpace (org.jetbrains.kotlin.com.intellij.psi.impl.source.tree.LeafPsiElement and org.jetbrains.kotlin.com.intellij.psi.PsiWhiteSpace are in unnamed module of loader org.codehaus.plexus.classworlds.realm.ClassRealm @7a639ec5)
    at org.cqfn.diktat.ruleset.rules.files.IndentationRule.visitWhiteSpace (IndentationRule.kt:165)
    at org.cqfn.diktat.ruleset.rules.files.IndentationRule.access$visitWhiteSpace (IndentationRule.kt:57)
    at org.cqfn.diktat.ruleset.rules.files.IndentationRule$checkIndentation$1.invoke (IndentationRule.kt:156)
    at org.cqfn.diktat.ruleset.rules.files.IndentationRule$checkIndentation$1.invoke (IndentationRule.kt:57)

Environment information

• diktat version: 0.1.3
• build tool (maven/gradle): maven
• how is diktat run (CLI, plugin, etc.): plugin
• kotlin version: 1.4.10

[petertrr]

Also, it shouldn't be trying to insert an empty line if there is no more text after tag's body.