[UAT-72] Unable to run Heatmap on RNAseq data

Added the same trick as for mRNA (59ca75141846f594bfeeb9e2fb0cfc92b5b0e308)
Merge pull request #4 from thehyve/issues/san-72-rnaseq-rows-with-same-annot

[UAT-72] Unable to run Heatmap on RNAseq data