gitolite: Redirect or close several projects for Network Team

Greetings,

The following can simply be closed without any redirections:

• https://gitweb.torproject.org/testnet.git/
• https://gitweb.torproject.org/tor-rust-dependencies.git/

The following should be redirected:

• https://gitweb.torproject.org/fallback-scripts.git/ -> https://gitlab.torproject.org/tpo/core/fallback-scripts
• https://gitweb.torproject.org/chutney.git/ -> https://gitlab.torproject.org/tpo/core/chutney
• https://gitweb.torproject.org/fuzzing-corpora.git/ -> https://gitlab.torproject.org/tpo/core/fuzzing-corpora
• https://gitweb.torproject.org/trunnel.git/ -> https://gitlab.torproject.org/tpo/core/trunnel