Rename `hbp-*` packages to `ebrains-*`

The following EBRAINS tools:

• py-hbp-archive
• py-hbp-neuromorphic-platform
• py-hbp-validation-client

need to be renamed to sth that doesn't include hbp.

For backwards compatibility, the old packages will also be kept for a certain time.

marked the checklist item py-hbp-validation-client as completed

already done for py-hbp-validation-client in !590 (merged)