Depends on qdrant/quantization#21.

This pull request adds Manhattan (L1, taxicab) as a 4th distance type (related to #3052). I am aware that this is an ambitious pull request as a first contribution, but I need the functionality and I think it has a justified place in the product.

The related issue mentions generalized Lp, but I thought it did not make much sense to try to implement AVX/SSE/Neon versions for it.

I have tried to follow the Euclid distance implementation as close as I could and I have copied the tests related to Euclid distance and converted them to Manhattan distance tests. I have also created an OpenAPI integration test for it.

I have implemented all AVX, SSE and Neon optimized similarity functions, they are all tested on proper hardware.

This pull request depends on the changes on the matching pull request at qdrant/quantization repo.

Once the branch at qdrant/quantization is merged, its dependency should be switched back to its usual form.

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