[lldb] Fix 'session save' command on Windows

1. Use dashes (-) instead of colons (:) as time separator in a session log
file name since Windows doesn't support saving files with names containing
colons.

2. Temporary file creation code is changed in the test:
On Windows, the temporary file should be closed before 'session save'
writes session log to it. NamedTemporaryFile() can preserve the file
after closing it with delete_on_close=False option.
However, this option is only available since Python 3.12. Thus
mkstemp() is used for temporary file creation as the more compatible
option.

Author: dzhidzhoev

lldb/source/Interpreter/CommandInterpreter.cpp

@@ -3235,6 +3235,8 @@ bool CommandInterpreter::SaveTranscript(
   if (output_file == std::nullopt || output_file->empty()) {
     std::string now = llvm::to_string(std::chrono::system_clock::now());
     std::replace(now.begin(), now.end(), ' ', '_');
+    // Can't have file name with colons on Windows
+    std::replace(now.begin(), now.end(), ':', '-');
     const std::string file_name = "lldb_session_" + now + ".log";
 
     FileSpec save_location = GetSaveSessionDirectory();

lldb/test/API/commands/session/save/TestSessionSave.py

@@ -19,7 +19,6 @@ def raw_transcript_builder(self, cmd, res):
             raw += res.GetError()
         return raw
 
-    @skipIfWindows
     @no_debug_info_test
     def test_session_save(self):
         raw = ""
@@ -61,8 +60,7 @@ def test_session_save(self):
         self.assertFalse(res.Succeeded())
         raw += self.raw_transcript_builder(cmd, res)
 
-        tf = tempfile.NamedTemporaryFile()
-        output_file = tf.name
+        output_file = self.getBuildArtifact('my-session')
 
         res = lldb.SBCommandReturnObject()
         interpreter.HandleCommand("session save " + output_file, res)
@@ -95,7 +93,6 @@ def test_session_save(self):
             for line in lines:
                 self.assertIn(line, content)
 
-    @skipIfWindows
     @no_debug_info_test
     def test_session_save_on_quit(self):
         raw = ""