Purge cached verdicts in sock_addr when the corrresponding filter_context is deleted.

1. When a filter context is deleted, all the corresponding verdicts that were cached should be deleted.
2. `_net_ebpf_ext_purge_blocked_connect_contexts()` currently is called only when the verdict is BLOCK. It should be called even in allow case, as this will clean up the queue sooner.

Start by locating the sock_addr filter-context deletion path and _net_ebpf_ext_purge_blocked_connect_contexts(). Trace how cached verdicts and the BLOCK and allow paths are handled. Done means deleting all verdicts associated with a deleted filter context and invoking the purge in both verdict cases, with the relevant tests passing.

Written by the indexing model from the issue text.