roomba error when installing roomba

Hi, thanks for a great package. I get the following error when installing roomba. @bretsw got the same error when doing this, too.

> devtools::install_github("ropenscilabs/roomba")
Using github PAT from envvar GITHUB_PAT
Downloading GitHub repo ropenscilabs/roomba@HEAD
These packages have more recent versions available.
It is recommended to update all of them.
Which would you like to update?

1: All                          
2: CRAN packages only           
3: None                         
4: dplyr (1.0.0 -> 1.0.1) [CRAN]

Enter one or more numbers, or an empty line to skip updates:
✓  checking for file ‘/private/var/folders/xd/xrgmmrv97355mcjtmjqcr72w0000gp/T/RtmpY8sBFU/remotes81353287bca2/ropenscilabs-roomba-ef3b84f/DESCRIPTION’ ...
─  preparing ‘roomba’:
✓  checking DESCRIPTION meta-information ...
   Warning in grepl(e, files, perl = TRUE, ignore.case = TRUE) :
     PCRE pattern compilation error
   	'unrecognized character follows \'
   	at 'images$'
   Error in grepl(e, files, perl = TRUE, ignore.case = TRUE) : 
     invalid regular expression '^\images$'
   Execution halted
Error: Failed to install 'roomba' from GitHub:
  System command 'R' failed, exit status: 1, stdout + stderr:
E> * checking for file ‘/private/var/folders/xd/xrgmmrv97355mcjtmjqcr72w0000gp/T/RtmpY8sBFU/remotes81353287bca2/ropenscilabs-roomba-ef3b84f/DESCRIPTION’ ... OK
E> * preparing ‘roomba’:
E> * checking DESCRIPTION meta-information ... OK
E> Warning in grepl(e, files, perl = TRUE, ignore.case = TRUE) :
E>   PCRE pattern compilation error
E> 	'unrecognized character follows \'
E> 	at 'images$'
E> Error in grepl(e, files, perl = TRUE, ignore.case = TRUE) : 
E>   invalid regular expression '^\images$'
E> Execution halted
>