Upgrade priority: Low. Recommended for users with long-running scripts.

Contributed:

• Fix rpc-provider LRU memory leak (Thanks to https://github.com/gdethier)

Changes:

• Don't warn on Lookup* types missing (these are resolvable)
• Don't clear injected PortableRegistry types on runtime upgrade
• Clear warning for Call/Event on non-meta v14 runtimes
• Add beefy_getFinalizedHead RPC support
• Update to latest Substrate, Kusama & Polkadot static metadata