Rename tests to fix docs

Recent changes to the configs meant our variable docs were getting built with the trackless EMPFlowSlim.json, which meant no track variables listed in the variable docs. Renamed the tests to that

• test-dumper pflow now runs something EMPFlow.json (similar to what it did before, but without the detailed truth)
• test-dumper slim now runs something EMPFlowSlim.json

For the docs we use test-dumper truth which uses EMPFlowTruth.json