Update assets/multiqc/deseq2_pca_header.txt

Co-authored-by: Matthias Hörtenhuber <mashehu@users.noreply.github.com>

assets/multiqc/deseq2_pca_header.txt

 #id: 'deseq2_pca'
 #section_name: 'MERGED LIB: DESeq2 PCA plot'
-#description: "PCA plot between samples in the experiment.
+#description: "PCA plot of the samples in the experiment.
 #              These values are calculated using <a href='https://bioconductor.org/packages/release/bioc/html/DESeq2.html'>DESeq2</a>
 #              in the <a href='https://github.com/nf-core/chipseq/blob/master/bin/deseq2_qc.r'><code>deseq2_qc.r</code></a> script."
 #plot_type: 'scatter'