report: Clarify loci filter precedence in QC_Report.docx (issue #288)

[jaamarks]

PR #305 (issue #288) changed the order of call rate filters to apply loci filters first.
This PR adds context to those changes in the QC_Report.docx.

Old

A two-stage filter by completion rate threshold of 0.80 for samples and 0.80 for loci, followed by 0.95 for samples and 0.95 for loci was performed. The first stage excluded 9 samples, and 6,498 loci. The subsequent filter excluded 40 samples and 23,799 loci, resulting in 451 samples at 708,734 loci (Table 2).

New

A two-stage filter was performed, applying loci filters followed by sample filters at each stage. The initial stage utilized a completion rate threshold of 0.80 for loci and 0.80 for samples. This resulted in the exclusion of 6,498 loci and 9 samples. The subsequent filter excluded 23,799 loci and 40 samples resulting in 451 samples at 708,734 loci (Table 2).