Devcontainer: Use latest Fedora 40 image

[osteffenrh]

Description

Since the CI is now running on Fedora 40, let's also switch over VSCode Devcontainer to use the same.

• Breaking change?
  • Breaking change - Does this PR cause a break in build or boot behavior?
  • Examples: Does it add a new library class or move a module to a different repo.
• Impacts security?
  • Security - Does this PR have a direct security impact?
  • Examples: Crypto algorithm change or buffer overflow fix.
• Includes tests?
  • Tests - Does this PR include any explicit test code?
  • Examples: Unit tests or integration tests.

How This Was Tested

Untested - I have trouble getting the VSCode Devcontainer extension to work.
Can some regular VSCode user please try this?

Integration Instructions

[tianocore-assign-reviewers]

⚠ WARNING: Cannot add some reviewers: A user specified as a reviewer for this PR is not a collaborator of the repository. Please add them as a collaborator to the repository so they can be requested in the future.

Non-collaborators requested:

• @Javagedes

Attn Admins:

• @jljusten
• @ardbiesheuvel
• @lgao4
• @mdkinney
• @jkmathews
• @miki-intel-work

---

Admin Instructions:

• Add the non-collaborators as collaborators to the appropriate team(s) listed in teams
• If they are no longer needed as reviewers, remove them from Maintainers.txt

[osteffenrh]

@makubacki ?

[makubacki]

@osteffenrh, you can open this easily without having VS Code installed.

1. Go to the branch - https://github.com/osteffenrh/edk2/tree/devcontainer-f40
2. Click "<> Code>. Click "Create codespace on ".
   
3. Wait for the codespace to be set up in your browser...
   
4. You should now be in the container.
   
5. You can run tests in the terminal at the bottom.
   • Setup (Clone)
     
   • Update (Pull Binary Dependencies)
     
   • Build / Test
     

[osteffenrh]

Interesting! I'll try that.