POT files generation issues

[Selenyhr]

Describe the bug
When generating POT files, there are two issues, one of which is due to Godot 4.1:

• import lines are included in the POT file ;
• quotes are not correctly escaped.

Affected version

• Dialogue Manager version: v2.27.3
• Godot version: v4.1.2.stable.arch_linux

To Reproduce
Use any file with a import line, and export POT files:

import "res://examples/dialogue.dialogue" as dialogue

Use any file where quotes are used within dialogues:

~ start
Nathan: This sentence contains "quotes."
=> END

Expected behavior
Import lines are not included in the POT file.

The other issue has been fixed in godotengine/godot#80058, however it may be nice to have some sort of forward-compatible fix for the quotes issue.

I will make a PR with a fix proposal. Could you try and make sure #365 will not include the new using syntax in the POT files please? :)