Using upper case schemas do not correctly

[mitar]

During tests we generate random schema names so that we can run tests in parallel. We generated them based on the regex in river, which allows upper case letters. The problem is that river migrations do not quote schemas (nor table names) so PostgreSQL internally converts them all to lowercase. Which can lead to conflicting schemas where we would expect that they would be independent. Resulting in flaky tests.

Or migration scripts should quote schemas or only lower case schemas should be allowed.

[brandur]

Put in a fix over in #1175.