[chronik] Add new endpoint to check chronik version

Summary: Add new endpoint /chronik-info to check the version of the currently running chronik-client server

Test Plan:
cmake .. -GNinja -DBUILD_BITCOIN_CHRONIK=ON
ninja check-functional

Reviewers: #bitcoin_abc, PiRK, Fabien

Reviewed By: #bitcoin_abc, PiRK, Fabien

Subscribers: Fabien, PiRK

Differential Revision: https://reviews.bitcoinabc.org/D14695