UI: make external text editor presets upper case

The presets for external text editors introduced in e16ec95a16 are
stored in Python files. The names of these files are used to generate
the UI name, and are case-sensitive.

They are currently lower case, but should be title case like other
presets. This commit renames the files so they are title case.

Pull Request: https://projects.blender.org/blender/blender/pulls/110642

scripts/presets/text_editor/visual_studio_code.py

@@ -1,12 +0,0 @@
-import bpy
-import platform
-
-filepaths = bpy.context.preferences.filepaths
-
-filepaths.text_editor_args = "-g $filepath:$line:$column"
-
-match platform.system():
-    case "Windows":
-        filepaths.text_editor = "code.cmd"
-    case _:
-        filepaths.text_editor = "code"