SONARIAC-2499 Docker analyzer should not fail to parse file endings with RUN instruction that ends with backslashes (#662)

GitOrigin-RevId: 3fe63e69d82597e205296af284ff275a04a553ee

Author: maksim-grebeniuk-sonarsource

iac-extensions/docker/src/main/java/org/sonar/iac/docker/parser/SourceCodeFinder.java

@@ -52,6 +52,9 @@ public String findSourceCode(TextPointer from, TextPointer to) {
 
     var nodeSource = IntStream.rangeClosed(startLine, endLine)
       .mapToObj(i -> {
+        if (i >= lines.size() && lines.get(lines.size() - 1).stripTrailing().endsWith("\\")) {
+          return "";
+        }
         var line = lines.get(i);
         int start = (i == startLine) ? startLineOffset : 0;
         int end = (i == endLine) ? endLineOffset : line.length();