Remove bogus logic in count query [DATAJPA-1635]

Jens Schauder opened DATAJPA-1635 and commented

PagedExecution.count contains the following logic:

			List<?> totals = repositoryQuery.createCountQuery(accessor).getResultList();
			return (totals.size() == 1 ? CONVERSION_SERVICE.convert(totals.get(0), Long.class) : totals.size());

Which doesn't make sense since a count query should always only return a single result and if it doesn't just counting the results won't yield a meaningful result.

Turns out this exists only due to a bug in some unit tests that use the mocked original query for the count query

Referenced from: pull request https://github.com/spring-projects/spring-data-jpa/pull/400, and commits https://github.com/spring-projects/spring-data-jpa/commit/b9e9c6b0a1262f1a973383430cf9574d058efd92, https://github.com/spring-projects/spring-data-jpa/commit/4dea8eb25702c88e631c6c5b0846f1edab26d9a6