Remove special assert syntax

[bplatz]

This code appears to create new flakes for @type values (classes) when being read from commits.

To my knowledge with the latest SID changes, this isn't needed and isn't done with initial transactions. At one point we did need a flake for every IRI, which is what I assume this was put in for.

I believe this would have the effect of a different db state for the same data when originally transacted vs read from commit files - as the latter would include flakes for every class, and the former would not.

After removing this code, all tests pass - but definitely want more eyeballs in case I'm missing something.

For a large commit, this code does a decent amount of work, so will help performance by removing it as well.

[zonotope]

This code looks like it's combining all the maps in an assert sequence with the same id in case you have something like {"@id" "ex:foo", "ex:friend" {"@id" "ex:bar", "ex:age" 27}}, and {"@id" "ex:bar", "ex:favColor" "green"} in the same sequence. i don't think we need this functionality either. since the tests pass, i say we get rid of it and deal with any issues when they come up.

👍🏾