Fixed that encoder may throws an from Throwable and not from Exception derived throwable

fints4k/src/commonMain/kotlin/net/dankito/banking/fints/messages/datenelemente/basisformate/TextDatenelement.kt

@@ -42,7 +42,7 @@ abstract class TextDatenelement(var value: String?, existenzstatus: Existenzstat
                         throwInvalidCharacterException()
                     }
                 }
-            } catch (e: Exception) {
+            } catch (e: Throwable) {
                 throwInvalidCharacterException()
             }
         }