Exclude all but one label for each ECA Problem to avoid redundant tasks

Proposed by @hoangmle, exclude all but one label for each ECA Problem, to avoid (almost) redundant tasks

Takes lots of computation time, shows no additional information compared to only one of each Problem

Proposed in https://github.com/sosy-lab/sv-benchmarks/pull/1019

Use subdirectory exclude for set-files that store task exclusions.