Bump ldk-node dependency

[jkczyz]

Bump the ldk-node dependency to support splicing.

[ldk-reviews-bot]

👋 Thanks for assigning @tnull as a reviewer!
I'll wait for their review and will help manage the review process.
Once they submit their review, I'll check if a second reviewer would be helpful.

[tnull]

Seems we'll need to check in a separate Cargo-minimal.lock file that we use for MSRV CI.

[jkczyz]

Ah, I usually run cargo with our MSRV, but hadn't done so here. Should I just build using cargo +1.75.0 for any Cargo.lock updates. Not sure what the best practices are.

[tnull]

Ah, I usually run cargo with our MSRV, but hadn't done so here. Should I just build using cargo +1.75.0 for any Cargo.lock updates. Not sure what the best practices are.

No, I think we want to keep the Cargo.lock on current stable and bump it now and then when we see a requirement. Most projects also check in a separate Cargo-minimal.lock file with the MSRV, see for example https://github.com/rust-bitcoin/rust-bitcoin/blob/master/Cargo-minimal.lock