Experiment with TrieMap for deduplicating `IfaceType`

In !12371 (closed), we introduced a deduplication table for deduplicating IfaceType values during interface file serialisation. See #24540 (closed) for the rationale.

The implementation uses Map IfaceType, as benchmarking seems to indicate this is more performant than using a TrieMap we have implemented in the branch: wip/fendor/ifacetype-triemap

The benchmarks were performed on the agda code base, and had little improvement, if any, over a simple Map IfaceType.

It would be interesting to analyse in more detail why TrieMap IfaceType is slower, and whether this can be fixed, as we can then drop the Ord IfaceType instance.