Define a common method to get an `IStore` instance from a string

[dahlia]

There are methods doing the similar thing in several places:

• Libplanet.Extensions.Cocona: StatsCommand.LoadStoreFromUri() method
• Libplanet.Extensions.Cocona: StoreCommand.LoadStoreFromUri() method
• Libplanet.Explorer.Executable: Program.LoadStore() method

What they do is to instantiate an implementation of IStore from a given string. Not only for getting rid of code duplication, but also for establishing a standard-ish format to referring Libplanet stores[^1], it's good to have a common method to do this. If we have a shared format for it, we can utilize it elsewhere as well, for example, configuration files.

[^1]: Think of JDBC URLs or ODBC connection strings.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. Thank you for your contributions.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. Thank you for your contributions.