make isDeclaration() match previous behavior

ktlint-ruleset-standard/src/main/kotlin/com/pinterest/ktlint/ruleset/standard/rules/SpacingBetweenDeclarationsWithCommentsRule.kt

@@ -1,6 +1,7 @@
 package com.pinterest.ktlint.ruleset.standard.rules
 
 import com.pinterest.ktlint.rule.engine.core.api.AutocorrectDecision
+import com.pinterest.ktlint.rule.engine.core.api.ElementType.SCRIPT_INITIALIZER
 import com.pinterest.ktlint.rule.engine.core.api.RuleId
 import com.pinterest.ktlint.rule.engine.core.api.SinceKtlint
 import com.pinterest.ktlint.rule.engine.core.api.SinceKtlint.Status.EXPERIMENTAL
@@ -15,6 +16,7 @@ import com.pinterest.ktlint.rule.engine.core.api.prevSibling
 import com.pinterest.ktlint.ruleset.standard.StandardRule
 import org.jetbrains.kotlin.com.intellij.lang.ASTNode
 import org.jetbrains.kotlin.com.intellij.psi.impl.source.tree.LeafElement
+import org.jetbrains.kotlin.psi.KtDeclarationImpl
 import org.jetbrains.kotlin.psi.stubs.elements.KtTokenSets
 
 /**
@@ -56,7 +58,11 @@ public class SpacingBetweenDeclarationsWithCommentsRule : StandardRule("spacing-
             }
     }
 
-    private fun ASTNode?.isDeclaration() = this != null && elementType in KtTokenSets.DECLARATION_TYPES
+    /**
+     * [KtScriptInitializer] is considered a type of declaration in terms of it being a subtype of [KtDeclarationImpl] even though SCRIPT_INITIALIZER is not included in DECLARATION_TYPES. We consider SCRIPT_INITIALIZER a declaration here to match previous behavior of ktlint in older versions.
+     */
+    private fun ASTNode?.isDeclaration() =
+        this != null && (elementType in KtTokenSets.DECLARATION_TYPES || elementType == SCRIPT_INITIALIZER)
 }
 
 public val SPACING_BETWEEN_DECLARATIONS_WITH_COMMENTS_RULE_ID: RuleId = SpacingBetweenDeclarationsWithCommentsRule().ruleId