ci: new artifact branches.list

Also change the filename generation pattern. Allowed characters are 0-9a-zA-Z and ., all other are replaced with underscore _.

Example branches.list:

23.12
24.1
build_from_source
can_vote_documentation
ci_ver
example_fix
f_alexandrov_change_config_description
devel
normalize_code_examples
pico_roles
rosik_branches.list_with_weird_name_1.2.3
sql_procedures
tiers_and_can_vote
tiers_in_deploy_md
update_sql_queries
validate_system_tables

---

• Related to https://git.picodata.io/picodata/web-site/infra/-/issues/2#note_65545
• Supersedes !317 (closed)
• Target branch: main
• Changes should be cherry-picked to 24.1: no
• Staging: https://docs.binary.picodata.io/picodata/rosik_branches.list_with_weird_name_1.2.3