Add slog benchmark and bump minimum Go version to 1.24
Relates to LabKit slog is slower and allocates more than v... (#91).
We can use 1.24 as a minimum version because Go 1.23 and even 1.24 are no longer supported versions. Omnibus and CNG now use 1.25 (&19848 (comment 3081019439)).
Edited by Mikhail Mazurskiy