[bug] panic when call RadixTree::try_remove

[yukkit]

The application panicked (crashed).
Message:  assertion failed: self.children_hdr.is_data() || self.children_hdr.is_none()
Location: /Users/yukkit/.cargo/registry/src/index.crates.io-6f17d22bba15001f/radixdb-0.2.5/src/node/mod.rs:894

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                                ⋮ 13 frames hidden ⋮                              
  14: core::panicking::panic::h4dc156260df6cc2f
      at /rustc/696aaad58c57a589f6fb2ecff5bae2eec581cb71/library/core/src/panicking.rs:117
  15: radixdb::node::TreeNode<S>::canonicalize::h507cf8dc2d1e74f5
      at /Users/yukkit/.cargo/registry/src/index.crates.io-6f17d22bba15001f/radixdb-0.2.5/src/node/mod.rs:894
  16: radixdb::node::left_combine_with::ha809223ab3766bcc
      at /Users/yukkit/.cargo/registry/src/index.crates.io-6f17d22bba15001f/radixdb-0.2.5/src/node/mod.rs:2718
  17: radixdb::node::left_combine_children_with::haf4a3ef8ca761f3d
      at /Users/yukkit/.cargo/registry/src/index.crates.io-6f17d22bba15001f/radixdb-0.2.5/src/node/mod.rs:2752
  18: radixdb::node::left_combine_with::ha809223ab3766bcc
      at /Users/yukkit/.cargo/registry/src/index.crates.io-6f17d22bba15001f/radixdb-0.2.5/src/node/mod.rs:2708
  19: radixdb::node::left_combine_children_with::haf4a3ef8ca761f3d
      at /Users/yukkit/.cargo/registry/src/index.crates.io-6f17d22bba15001f/radixdb-0.2.5/src/node/mod.rs:2752
  20: radixdb::node::left_combine_with::ha809223ab3766bcc
      at /Users/yukkit/.cargo/registry/src/index.crates.io-6f17d22bba15001f/radixdb-0.2.5/src/node/mod.rs:2708
  21: radixdb::node::<impl radixdb::RadixTree<S>>::try_left_combine_with::h23565af36f6e5b9c
      at /Users/yukkit/.cargo/registry/src/index.crates.io-6f17d22bba15001f/radixdb-0.2.5/src/node/mod.rs:3734
  22: radixdb::node::<impl radixdb::RadixTree<S>>::try_remove::hf42c166de4dbad23
      at /Users/yukkit/.cargo/registry/src/index.crates.io-6f17d22bba15001f/radixdb-0.2.5/src/node/mod.rs:3535
  23: tskv::index::engine::IndexEngine::delete::hc53ba8d07cfe7f1b
      at /Users/yukkit/VCWorkspace/cnosdb/tskv/src/index/engine.rs:146

[rklaehn]

There is an invariant that was violated. Definitely a bug.

Can you try to come up with a small reproducer?