pkgdown build error

:wave: @martinezc1! On https://ropensci.r-universe.dev/builds we see

```r
Reading paper.md
Error parsing YAML metadata at "/__w/ropensci/ropensci/paper.md" (line 1, column 1):
YAML parse exception at line 12, column 1,
while parsing a block collection:
did not find expected '-' indicator
```