Eliminate Trimmomatic from pipeline

[willbradshaw]

Trimmomatic is much slower and more compute-hungry than the other adapter-trimming tools we use in the pipeline, and represents a significant fraction of total CPU-hours for many runs. We should eliminate it from the pipeline, either by reconfiguring another tool we already use (e.g. FASTP) or adding a new tool to replace it. However, this will require careful QC to check that we're not introducing new false positives into the final pipeline output.