Some code cleanup

[wezrule]

seq_con_info is not fully accurate, because there are many containers that are used not just sequence (vector, list etc..), such as maps. Changed it to be container_info.

I started a trend of using namespace nano guards around the collect_seq_con_info functions. We don't do this anywhere else (and I think that should stay the case). So adding the nano namespace qualifier to these functions i.e nano::.... Also arranged the contents of those functions to be more consistent with each other and removed any = 0 count initialises because they are always set later so it's redundant.

config.hpp
No need for static, as const variables implicitly have static linakge already (of course you need the "pointer to constant data" form too: const char* const str)

core_test/rpc.cpp
The rpc.database_txn_tracker test was not being run when building with rocksdb regardless of the TEST_USE_ROCKSDB env variable, it should only be disabled if actually using it.

Some tests were missing ASSERT_NO_ERROR around system.poll () and some system.deadline_set () calls before them too.

core_test/locks.cpp
I had built with a ridiculously high NANO_TIMED_LOCKS value, without even realising, then noticed the locks tests appearing to stall. This is just because they do a sleep for the NANO_TIMED_LOCKS length inside the test, so I'm now failing the test if it is greater than 10 seconds just so that they can finish at least.