chore: 🤖 [JIRA:HCPSDKFIORIUIKIT-2827]cleanup warning

Stored property 'chartType' of 'Sendable'-conforming struct
'ColumnChartCategoryShape' has non-sendable type 'ChartType'; this is an
error in the Swift 6 language mode

Sources/FioriCharts/Model/ChartType.swift

@@ -1,7 +1,7 @@
 import Foundation
 
 /// Available chart types. Use this enum to define chart type to present.
-public enum ChartType: String {
+public enum ChartType: String, Sendable {
     /// Line Chart
     case line