Fix for string based codingkeys

Author: Wouter01

Sources/swift-csv/AsyncCodableCSVIterator.swift

@@ -49,7 +49,7 @@ public struct AsyncCodableCSVIterator<T: Decodable, Encoding: _UnicodeEncoding>:
 
         self.iterator = iterator
         self.headers = iterator.headers
-        self.lineDecoder = CSVLineDecoder(data: .init(booleanDecodingBehavior: booleanDecodingBehavior))
+        self.lineDecoder = CSVLineDecoder(data: .init(headers: iterator.headers, booleanDecodingBehavior: booleanDecodingBehavior))
     }
 
     public mutating func next() async throws -> Element? {

Sources/swift-csv/CSVLineDecoder.swift

@@ -40,7 +40,8 @@ extension CSVLineDecoder {
         var tempData: [String] = []
         let booleanDecodingBehavior: BooleanDecodingBehavior
 
-        init(booleanDecodingBehavior: BooleanDecodingBehavior) {
+        init(headers: [String]?, booleanDecodingBehavior: BooleanDecodingBehavior) {
+            self.headers = headers
             self.booleanDecodingBehavior = booleanDecodingBehavior
         }
     }