bug: cannot publish empty data.frame

**Describe the bug**

Cannot publish an empty dataframe related to #286 

**To Reproduce**

```r
library(arcgis)

set_arc_token(auth_user())

empty_df <- penguins[0,]

res <- publish_layer(empty_df, "empty_test")
```


**Expected behavior**

An empty data.frame has useful information and should be able to be used to publish

