chore: Resolve Compiler Warning

Resolves the following warning: Using 'getter for first: E!' is an error.
'getFirst()' member of List is redundant in Kotlin and might be removed
soon. Please use 'first()' stdlib extension instead.
The snippet itself is not using "getFirst" or "first" but the correctly
stated "first()" method. Therefore it seems to be a false positive.

Author: wba2hi

kuksa-java-sdk/src/main/kotlin/org/eclipse/kuksa/extension/vss/VssNodeCopyExtension.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2023 Contributors to the Eclipse Foundation
+ * Copyright (c) 2023 - 2025 Contributors to the Eclipse Foundation
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -14,6 +14,7 @@
  * limitations under the License.
  *
  * SPDX-License-Identifier: Apache-2.0
+ *
  */
 
 package org.eclipse.kuksa.extension.vss
@@ -57,7 +58,8 @@ fun <T : VssNode> T.deepCopy(generation: Int = 0, changedHeritage: List<VssNode>
     // Create the missing link between this [VssNode] and the given node inbetween
     var heritageLine = changedHeritage
     if (changedHeritage.size == 1) {
-        heritageLine = findHeritageLine(changedHeritage.first(), true)
+        val heir = changedHeritage.firstOrNull()!! // safe cast to non-null because size == 1
+        heritageLine = findHeritageLine(heir, true)
             .toList()
             .ifEmpty { changedHeritage }
     }