new profile for ender3 extender 400xl

[jtrauger]

Description

This change adds a new profile for an ender3 with the 400xl extender mod from enderextender.com

Type of change

• Printer definition file(s)

How Has This Been Tested?

• Test A - Added relavant files to my C:\Program Files\UltiMaker Cura 5.7.0\share\cura\resources directory and created new printer. Verified printer showed up as expected with new larger size and background mesh
• Test B - ran a test print which was sliced for this machine

Test Configuration:

• Operating System:
  Windows 10

Checklist:

• My code follows the style guidelines of this project as described in UltiMaker Meta and Cura QML best practices
• I have read the Contribution guide
• I have commented my code, particularly in hard-to-understand areas
• I have uploaded any files required to test this change