Should we have the tests skipped if the dependencies are missing? (RocksDB to be specific)

[tkiapril]

Currently, parts of test codes related to RocksDB are skipped if RocksDB is unavailable:

• https://github.com/planetarium/libplanet/blob/main/Libplanet.Extensions.Cocona.Tests/Commands/StoreCommandTest.cs#L41-L51
• https://github.com/planetarium/libplanet/blob/main/Libplanet.RocksDBStore.Tests/RocksDBStoreTest.cs#L24-L33

This might be of ease developing on local platforms without support, but these kinds of skipped tests also affect the CI, skipping the tests unknowingly if there are missing dependencies. As a matter of fact, tests using RocksDBStore were being skipped on the CI with linux-netcore jobs. (Fixed with #2156)

Thus, we would have to decide how we will deal with tests of this sort, whether it is problematic and we should have it fail as is if there are missing dependencies.

My two cents are to have them fail regardless, since they are not to be run in the first place if the dependencies are missing. It would be easier to detect if there's anything wrong on the CI.

Related: #974