Fix metadata read

[miratepuffin]

What changes were proposed in this pull request?

Why are the changes needed?

Does this PR introduce any user-facing change? If yes is this documented?

How was this patch tested?

Are there any further changes required?

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'Rust Benchmark'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 2.

Benchmark suite	Current: 8448a1c	Previous: 9823ef7	Ratio
lotr_graph/num_edges	5 ns/iter (± 0)	0 ns/iter (± 0)	+∞
lotr_graph/num_nodes	5 ns/iter (± 0)	1 ns/iter (± 0)	5
lotr_graph/graph_latest	3 ns/iter (± 0)	0 ns/iter (± 0)	+∞
lotr_graph_materialise/materialize	7715140 ns/iter (± 82321)	1564816 ns/iter (± 35303)	4.93
lotr_graph_window_100/num_nodes	14 ns/iter (± 0)	5 ns/iter (± 0)	2.80
lotr_graph_window_100/iterate_exploded_edges	751032 ns/iter (± 5224)	325242 ns/iter (± 847)	2.31
lotr_graph_window_100_materialise/materialize	8433618 ns/iter (± 90775)	1669150 ns/iter (± 10700)	5.05
lotr_graph_window_10/has_edge_existing	196 ns/iter (± 9)	97 ns/iter (± 11)	2.02
lotr_graph_window_10/has_node_existing	144 ns/iter (± 7)	62 ns/iter (± 11)	2.32
lotr_graph_window_10/iterate nodes	32317 ns/iter (± 108)	11339 ns/iter (± 40)	2.85
lotr_graph_window_10/iterate edges	100219 ns/iter (± 1798)	48684 ns/iter (± 211)	2.06
lotr_graph_window_10/iterate_exploded_edges	383630 ns/iter (± 1014)	155788 ns/iter (± 1001)	2.46
lotr_graph_window_10_materialise/materialize	3557041 ns/iter (± 18682)	971980 ns/iter (± 4278)	3.66
lotr_graph_subgraph_10pc_materialise/materialize	1580372 ns/iter (± 11749)	334634 ns/iter (± 1287)	4.72
lotr_graph_subgraph_10pc_windowed/has_node_existing	147 ns/iter (± 8)	62 ns/iter (± 14)	2.37
lotr_graph_subgraph_10pc_windowed/iterate nodes	5163 ns/iter (± 92)	1365 ns/iter (± 3)	3.78
lotr_graph_subgraph_10pc_windowed_materialise/materialize	947985 ns/iter (± 20664)	230399 ns/iter (± 2617)	4.11
lotr_graph_window_50_layered/num_edges_temporal	151967 ns/iter (± 2555)	70121 ns/iter (± 7586)	2.17
lotr_graph_window_50_layered/has_node_existing	419 ns/iter (± 19)	129 ns/iter (± 12)	3.25
lotr_graph_window_50_layered/iterate nodes	74995 ns/iter (± 448)	19308 ns/iter (± 47)	3.88
lotr_graph_window_50_layered/iterate edges	193528 ns/iter (± 475)	83616 ns/iter (± 1318)	2.31
lotr_graph_window_50_layered/graph_latest	77705 ns/iter (± 1764)	36649 ns/iter (± 916)	2.12
lotr_graph_window_50_layered_materialise/materialize	26107189 ns/iter (± 275840)	3488825 ns/iter (± 24948)	7.48
lotr_graph_persistent_window_50_layered/num_edges_temporal	598970 ns/iter (± 3883)	192686 ns/iter (± 1569)	3.11
lotr_graph_persistent_window_50_layered/has_node_existing	460 ns/iter (± 284)	174 ns/iter (± 83)	2.64
lotr_graph_persistent_window_50_layered/iterate nodes	97529 ns/iter (± 411)	35886 ns/iter (± 191)	2.72
lotr_graph_persistent_window_50_layered/iterate_exploded_edges	4193211 ns/iter (± 28230)	1659940 ns/iter (± 19402)	2.53
lotr_graph_persistent_window_50_layered_materialise/materialize	47742126 ns/iter (± 129877)	5298035 ns/iter (± 147912)	9.01
lotr_graph/proto_encode	9163136 ns/iter (± 38913)	1157897 ns/iter (± 73709)	7.91

This comment was automatically generated by workflow using github-action-benchmark.

[fabubaker]

LGTM

[fabubaker]

check_metadata_immut seems more consistent with the other methods but not a blocker.