set VERSION to 1.12.5

`release-1.11`: Set VERSION to 1.11.9 (JuliaLang#60840)

set VERSION to 1.13.0-beta2 (JuliaLang#60912)

set VERSION to 1.13.0-beta1 (JuliaLang#60613)

set VERSION to 1.12.4 (JuliaLang#60539)

set VERSION to 1.13.0-alpha2 (JuliaLang#60280)

Backports for 1.12.3 (JuliaLang#60225)

set VERSION to 1.13.0-alpha1 (JuliaLang#60151)

set VERSION to 1.12.2 (JuliaLang#60182)

Co-authored-by: KristofferC <kristoffer.carlsson@juliacomputing.com>

`release-1.11`: Set `VERSION` to `1.11.8` (JuliaLang#60028)

cc: @KristofferC