Fix panic when backup bootstrap peer load and save funcs are nil
A panic occurs when the first bootstrap round runs is these functions are not assigned in the configuration:
- `LoadBackupBootstrapPeers`
- `SaveBackupBootstrapPeers`
This fix assumes that it is acceptable for these functions to be nil, as it may be desirable to disable the backup peer load and save functionality.
* feat(bootstrap): save connected peers as backup temporary bootstrap ones
* fix: do not add duplicated oldSavedPeers, not using tags, reuse
randomizeList
* test: add regression test
* chore: add changelog
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Co-authored-by: Henrique Dias <hacdias@gmail.com>
Co-authored-by: Marcin Rataj <lidel@lidel.org>
