Make report.Rmd knit by updating old variable name
Make report.Rmd knit by updating old variable name

The period_code variable as updated to most_recent_period in
b8fe02229019bf6543550d36e2dbf3820cec2158. One use got missed which is causing
the file not to knit.

weecology/portalPredictions,gmyenni/portalPredictions,weecology/portalPredictions,sdtaylor/portalPredictions,gmyenni/portalPredictions,sdtaylor/portalPredictions,gmyenni/portalPredictions,sdtaylor/portalPredictions,weecology/portalPredictions