Context

Because rpc.Environment does not store a GenesisDoc in memory anymore, (see #1290), we don't need to create it as a singleton. The risk of storing multiple copies of the genesis in memory isn't there anymore, because we now load it from disk.

This Change

This PR removes the sync.Once construct that we put in place.

Additional Note

The change also ensures that TestProvider in the light/provider/http package behaves as expected. In main, this test passes because it's set up using a MemDB, which is a dummy in-memory store rather than a real database. Thus, database Get operations always succeed.

However, in the context of the work to remove cometbft-db, we now use a "real" database, i.e., one that a Node closes when it shuts down. Since the Environment object was treated as a singleton, each iteration of TestProvider created a new Node using the same underlying database. This database would be closed at the end of the first iteration when that iteration's Node shut down. Subsequent iterations then attempted to call Get on a closed database, causing a panic.

This change fixes that issue.

PR checklist

• Tests written/updated
• Changelog entry added in .changelog (we use unclog to manage our changelog)
• [ ] Updated relevant documentation (docs/ or spec/) and code comments