OOME when there are large amounts of validation reports

[RickMoynihan]

e.g. running

$ clojure -M:pmd-qb:validate -e https://staging.gss-data.org.uk/sparql

In the pmd-rdf-validations repo.

I think one reason this may occur is because of this:

rdf-validator/src/rdf_validator/core.clj

Lines 92 to 93 in 5ecc5fa

	(defn run-test-cases [test-cases query-variables endpoint]
	(map #(run-test-case % query-variables endpoint) test-cases))

I suspect Clojure's batching of lazy seqs into 32 items might cause a space leak here if a test-case returns a large lazy sequence of test case errors then it may not be released. Out of curiousity I tried hacking this by putting a (take 1000) over the results inside the with-open which eagerly loads data into a vector, however it seemed the leak was still occuring, so I suspect there may be other issues here.

It may be worth rewriting this code to be eager using transducers, or to put a configurable limit over the amount of test failures to report on for any given test case.