Fix Windows build by adding llvm-tools dependency.

[acolwell]

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PR Description

What type of PR is this? (Check one of the boxes below)

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Improvement (non-breaking change which does not add functionality nor fixes a bug but improves Natron in some way)
• Breaking change (fix or feature that would cause existing functionality to change)
• My change requires a change to the documentation
  • I have updated the documentation accordingly

What does this pull request do?

Shiboken2 and Shiboken6 rely on llvm-config to find the location of clang and its include directory. Recently the clang package had llvm-config split out into a llvm-tools package. This change adds llvm-tools to Natron's build deps packages so that llvm-config will get installed when those packages are installed.

Have you tested your changes (if applicable)? If so, how?

Yes. Verified CI Tests , Windows Installer, and build pacman repo GitHub actions all successfully build again.