### Godot version

master

### System information

Win11

### Issue description

When use `Generate POT` for multiline texts, it drops `\n` and generates single line message.

- **Label text in Main.tscn:**
![image](https://user-images.githubusercontent.com/12966814/209623668-19fd1d76-038a-4c19-938e-7559eb7652a3.png)


- **tr() text in Main.gd:**
```gdscript
func _ready():
	print(tr("MULTILINE text\nfrom\nMain.gd"))
```

- **Generated .pot:**
```pot
#: Main.tscn
#: Main.gd
msgid "MULTILINE text"
"from"
"Main.gd"
msgstr ""

#: Main.tscn
msgid "This is"
"MULTILINE text"
"from Main.tscn"
msgstr ""
```
This is actually single line like `This isMULTILINE textfrom Main.tscn`


- **Expected:**

```pot
#: Main.tscn Main.gd
msgid ""
"MULTILINE text\n"
"from\n"
"Main.gd"
msgstr ""

#: Main.tscn
msgid ""
"This is\n"
"MULTILINE text\n"
"from Main.tscn"
msgstr ""
```

### Steps to reproduce

Generate pot file for multiline texts.


### Minimal reproduction project

[generate_pot_newline.zip](https://github.com/godotengine/godot/files/10306460/generate_pot_newline.zip)

#include "pot_generator.h"
#include "core/config/project_settings.h"
#include "core/error/error_macros.h"
#include "editor/editor_translation_parser.h"
#include "plugins/packed_scene_translation_parser_plugin.h"
POTGenerator *POTGenerator::singleton = nullptr;
#ifdef DEBUG_POT
void POTGenerator::_print_all_translation_strings() {
	for (HashMap<String, Vector<POTGenerator::MsgidData>>::Element E = all_translation_strings.front(); E; E = E.next()) {
		Vector<MsgidData> v_md = all_translation_strings[E.key()];
		for (int i = 0; i < v_md.size(); i++) {
			print_line("++++++");
			print_line("msgid: " + E.key());
			print_line("context: " + v_md[i].ctx);
			print_line("msgid_plural: " + v_md[i].plural);
			for (const String &F : v_md[i].locations) {
				print_line("location: " + F);
			}
		}
	}
}
#endif
void POTGenerator::generate_pot(const String &p_file) {