C#: Fixup test expectations from using stdin

Author: RasmusWL

csharp/ql/test/library-tests/dataflow/library/FlowSummaries.expected

@@ -183,10 +183,10 @@ source
 | System.IO;StreamWriter;StreamWriter;(System.String,System.IO.FileStreamOptions);Argument[this];file-write;manual |
 | System.IO;StreamWriter;StreamWriter;(System.String,System.Text.Encoding,System.IO.FileStreamOptions);Argument[this];file-write;manual |
 | System.Net.Sockets;TcpClient;GetStream;();ReturnValue;remote;manual |
-| System;Console;Read;();ReturnValue;local;manual |
-| System;Console;ReadKey;();ReturnValue;local;manual |
-| System;Console;ReadKey;(System.Boolean);ReturnValue;local;manual |
-| System;Console;ReadLine;();ReturnValue;local;manual |
+| System;Console;Read;();ReturnValue;stdin;manual |
+| System;Console;ReadKey;();ReturnValue;stdin;manual |
+| System;Console;ReadKey;(System.Boolean);ReturnValue;stdin;manual |
+| System;Console;ReadLine;();ReturnValue;stdin;manual |
 | System;Environment;ExpandEnvironmentVariables;(System.String);ReturnValue;environment;manual |
 | System;Environment;GetCommandLineArgs;();ReturnValue;commandargs;manual |
 | System;Environment;GetEnvironmentVariable;(System.String);ReturnValue;environment;manual |

csharp/ql/test/utils/modelgenerator/dataflow/Sources.cs

@@ -14,15 +14,15 @@ public class NewSources
 
 
     // New source
-    // source=Sources;NewSources;false;WrapConsoleReadLine;();;ReturnValue;local;df-generated
+    // source=Sources;NewSources;false;WrapConsoleReadLine;();;ReturnValue;stdin;df-generated
     // neutral=Sources;NewSources;WrapConsoleReadLine;();summary;df-generated
     public string? WrapConsoleReadLine()
     {
         return Console.ReadLine();
     }
 
     // New source
-    // source=Sources;NewSources;false;WrapConsoleReadLineAndProcees;(System.String);;ReturnValue;local;df-generated
+    // source=Sources;NewSources;false;WrapConsoleReadLineAndProcees;(System.String);;ReturnValue;stdin;df-generated
     // neutral=Sources;NewSources;WrapConsoleReadLineAndProcees;(System.String);summary;df-generated
     public string WrapConsoleReadLineAndProcees(string prompt)
     {
@@ -37,7 +37,7 @@ public string WrapConsoleReadLineAndProcees(string prompt)
     }
 
     // New source
-    // source=Sources;NewSources;false;WrapConsoleReadKey;();;ReturnValue;local;df-generated
+    // source=Sources;NewSources;false;WrapConsoleReadKey;();;ReturnValue;stdin;df-generated
     // neutral=Sources;NewSources;WrapConsoleReadKey;();summary;df-generated
     public ConsoleKeyInfo WrapConsoleReadKey()
     {