Bump LLVM to v19.1.7+1 (#56130)
Including #55650 till that's merged.
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Co-authored-by: Jameson Nash <vtjnash@gmail.com>
Co-authored-by: Mosè Giordano <m.giordano@ucl.ac.uk>
Co-authored-by: gbaraldi <baraldigabriel@gmail.com>
Co-authored-by: Mosè Giordano <765740+giordano@users.noreply.github.com>
