chore(deps): Bump reth

[emhane]

Based on #1094

• Bumps reth to v1.2.0
• Updates docs to reflect that ChainProvider is for L1 chain

[clabby]

Our MSRV in kona is rustc 1.81, needed to be able to support R0/SP-1 zkVM targets. @ratankaliani - have you guys been able to upgrade your target yet?

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.1%. Comparing base (4c30980) to head (419698d).

✅ All tests successful. No failed tests found.

Additional details and impacted files

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[refcell]

The rust MSRV needs to be bumped here to 1.82. We need to check in with Succinct and other downstream kona users to ensure this will work for them.

[ratankaliani]

We now support Rust 1.82, should be good to go to bump.

[refcell]

@clabby updated the MSRV in #1097.

Please rebase on trunk to include these changes :)