C#: Update expected test output.

Author: michaelnebel

csharp/ql/test/library-tests/csharp11/PrintAst.expected

@@ -599,6 +599,19 @@ Strings.cs:
 #   46|           -1: [TypeMention] string
 #   46|           0: [LocalVariableAccess] access to local variable y
 #   46|           1: [StringLiteralUtf16] "AUTH16: "
+#   49|       2: [LocalVariableDeclStmt] ... ...;
+#   49|         0: [LocalVariableDeclAndInitExpr] ReadOnlySpan<Byte> z = ...
+#   49|           -1: [TypeMention] ReadOnlySpan<byte>
+#   49|           0: [LocalVariableAccess] access to local variable z
+#   49|           1: [StringLiteralUtf8] "AUTH8: 
+#   49|                   <username> "
+#   53|       3: [LocalVariableDeclStmt] ... ...;
+#   53|         0: [LocalVariableDeclAndInitExpr] ReadOnlySpan<Byte> w = ...
+#   53|           -1: [TypeMention] ReadOnlySpan<byte>
+#   53|           0: [LocalVariableAccess] access to local variable w
+#   53|           1: [StringLiteralUtf8] "The nested message
+#   53|             is UTF-8 encoded and
+#   53|           spans multiple lines."
 cil/class1.cs:
 #    4| [Class] Class1
 #    6|   5: [Method] Main

csharp/ql/test/library-tests/csharp11/strings.expected

@@ -19,3 +19,5 @@ stringliterals
 | Strings.cs:35:57:35:57 | "}" | StringLiteralUtf16 | String |
 | Strings.cs:43:17:43:27 | "AUTH8: " | StringLiteralUtf8 | ReadOnlySpan<Byte> |
 | Strings.cs:46:17:46:26 | "AUTH16: " | StringLiteralUtf16 | String |
+| Strings.cs:49:17:50:22 | "AUTH8: \n        <username> " | StringLiteralUtf8 | ReadOnlySpan<Byte> |
+| Strings.cs:53:17:57:13 | "The nested message\n  is UTF-8 encoded and\nspans multiple lines." | StringLiteralUtf8 | ReadOnlySpan<Byte> |