[Chronik] Fix build for Windows, fix util/hash.h

Summary: The windows build fails because uint8_t is not defined, so we add #include <cstdint>.

Test Plan:
ninja
Run the CI windows build

Reviewers: Fabien, #bitcoin_abc

Reviewed By: Fabien, #bitcoin_abc

Subscribers: kongpcmail

Differential Revision: https://reviews.bitcoinabc.org/D13217