[LL API] Replace 'FirScript.containingFileSymbol' with 'FirProvider' API

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/NodeConfigurator.kt

@@ -475,9 +475,6 @@ object NodeConfigurator : AbstractFieldConfigurator<FirTreeBuilder>(FirTreeBuild
             +name
             +fieldList(statement).withTransform()
             +symbol("FirScriptSymbol")
-            +field("containingFileSymbol", type("fir.symbols.impl", "FirFileSymbol"), argument = null).apply {
-                withBindThis = false
-            }
             +FieldList("parameters", variable, withReplace = false)
             +fieldList(contextReceiver, useMutableOrEmpty = true)
         }