[R] Cannot install Arrow 22 to RHEL due to lack of escape characters in grepl

### Describe the bug, including details regarding any error messages, version, and platform.

Attempting to install arrow in RStudio Pro on Posit Workbench, AWS RHEL hosted, get the following error:

> install.packages("arrow")
Installing package into ‘/home/byw23/R/x86_64-pc-linux-gnu-library/4.3’
(as ‘lib’ is unspecified)
trying URL 'https://cloud.r-project.org/src/contrib/arrow_22.0.0.tar.gz'
Content type 'application/x-gzip' length 4238550 bytes (4.0 MB)
==================================================
downloaded 4.0 MB

* installing *source* package ‘arrow’ ...
** package ‘arrow’ successfully unpacked and MD5 sums checked
** using staged installation
*** pkg-config found.
Error in grepl(paste(allowlist, collapse = "|"), os) :
invalid regular expression, reason 'Invalid contents of {}'
Calls: identify_binary -> ifelse -> check_allowlist -> grepl
Execution halted
------------------------- NOTE ---------------------------
There was an issue building the Arrow C++ libraries.
See https://arrow.apache.org/docs/r/articles/install.html
---------------------------------------------------------
ERROR: configuration failed for package ‘arrow’
* removing ‘/home/USER/R/x86_64-pc-linux-gnu-library/4.3/arrow’
Warning in install.packages :
installation of package ‘arrow’ had non-zero exit status

The downloaded source packages are in
‘/tmp/RtmpsK2Blf/downloaded_packages’

Consultation with GPT shows that the issue is the parentheses in the OS name:
> sessionInfo()$running
[1] "Red Hat Enterprise Linux 9.6 (Plow)"

Can we add some escape characters to allow for things like spaces and parentheses in OS names?

### Component(s)

C++, R, Packaging