Remove unnecessary c++ compiler dependencies

We no longer need unf_ext and will remove use of eventmachine.

provision/provision-centos.sh

@@ -120,13 +120,10 @@ function install_native_build_packages() {
   # Ruby-build dependencies for ASDF: https://github.com/rbenv/ruby-build/wiki#centos
   try dnf -y install gcc patch bzip2 openssl-devel libyaml-devel libffi-devel readline-devel zlib-devel gdbm-devel ncurses-devel
 
-  # Ruby dependencies for building grpc due to https://github.com/grpc/grpc/issues/26391
+  # Ruby dependencies for building grpc due to https://github.com/grpc/grpc/issues/34595 and https://github.com/grpc/grpc/issues/26391
   if [ "$(arch)" == "aarch64" ]; then
     try dnf -y install libstdc++-static
   fi
-
-  # Ruby dependencies that need to build native extensions (no pre-built binaries)
-  try dnf -y install gcc-c++ # Required by unf_ext + eventmachine (try removing if no need for these)
 }
 
 function install_scm_tools() {