Feat: single table structure eval metric (#2655)
Creates a compounding metric to represent table structure score. It is
an average of existing row and col index and content score.
This PR adds a new property to
`unstructured.metrics.table_eval.TableEvaluation`:
`composite_structure_acc`, which is computed from the element level row
and column index and content accuracy scores. This new metric is meant
to offer a single number to represent the performance of table structure
extraction model/algorithms.
This PR also refactors the eval computation logic so it uses a constant
`table_eval_metrics` instead of hard coding the name of the metrics in
multiple places in the code.
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Co-authored-by: qued <64741807+qued@users.noreply.github.com>
