`find_external_resources` needs to consider quarto theme file

[cderv]

---
title: "Customer Tracker Report"
format:
  html:
    theme:
    - lux
    - custom.scss
---

```{r}
#| label: pulldata
# In real use case, this could be retrieved from databases query for the new date for example
curr <- readr::read_csv("data/trackerCalcCurr.csv")
pre <- readr::read_csv("data/trackerCalcPre.csv")
users <- readr::read_csv("data/users.csv")
```

Here find_external_resources should find custom.scss without requiring to add

resource_files:
- custom.scss

This would make rsconnect file dependency search to consider this file required to build document on deployed server