Delete `blockchain verify` command

Original title: tests are sometimes failing due to network outage

https://git.duniter.org/clients/python/silkaj/-/jobs/42791

FAILED tests/test_verify_blocks.py::test_get_chunks[2-1] - TypeError: 'NoneTy...
FAILED tests/test_verify_blocks.py::test_get_chunks[5-10] - TypeError: 'NoneT...

Edited Oct 21, 2023 by Moul

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information