fix: build with gcc 13.2.0 - missing header memory in addrdb

[knst]

Issue being fixed or feature implemented

In file included from test/addrman_tests.cpp:5:
./addrdb.h:51:99: error: ‘std::unique_ptr’ has not been declared
   51 | std::optional<bilingual_str> LoadAddrman(const std::vector<bool>& asmap, const ArgsManager& args, std::unique_ptr<AddrMan>& addrman);
      |                                                                                                   ^~~
./addrdb.h:51:114: error: expected ‘,’ or ‘...’ before ‘<’ token
   51 | std::optional<bilingual_str> LoadAddrman(const std::vector<bool>& asmap, const ArgsManager& args, std::unique_ptr<AddrMan>& addrman);
      |                    

What was done?

adds missing header <memory> in addrdb

How Has This Been Tested?

Run build - it works

Breaking Changes

N/A

Checklist:

• [x] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have added or updated relevant unit/integration/functional/e2e tests
• [ ] I have made corresponding changes to the documentation
• [x] I have assigned this pull request to a milestone