Update PT report naming practices

[kelliemac]

Description

Per discussion with Alicia and Bryan, updated PT report file naming format to VDCnnn_assay_PTreport_status_blindingifapplicable, for example:

• VDCnnn_BAMA_PTreport_interim_blinded.Rmd
• VDCnnn_BAMA_PTreport_interim_unblinded.Rmd
• VDCnnn_BAMA_PTreport_final.Rmd

Related Issues

Related to https://github.com/FredHutch/VISCtemplates/issues/98

Checklist

• [ ] This PR includes unit tests
• [ ] This PR establishes a new function or updates parameters in an existing function
  • [ ] The roxygen skeleton for this function has been updated using devtools::document
• [X] I have updated NEWS.md to describe the proposed changes