apacheGH-38049: [R] Prevent on_rosetta() from warning (apache#38052)

### Rationale for this change

Stop extraneous warnings.

### What changes are included in this PR?

Prevent warning when detecting translation, but on x86

### Are these changes tested?

Yes

### Are there any user-facing changes?

Yes, there will be fewer extraneous warnings.
* Closes: apache#38049

Authored-by: Jonathan Keane <jkeane@gmail.com>
Signed-off-by: Dewey Dunnington <dewey@voltrondata.com>

r/R/arrow-package.R

@@ -183,7 +183,7 @@ configure_tzdb <- function() {
   # Just to be extra safe, let's wrap this in a try();
   # we don't want a failed startup message to prevent the package from loading
   try({
-        # On MacOS only, Check if we are running in under emulation, and warn this will not work
+    # On MacOS only, Check if we are running in under emulation, and warn this will not work
     if (on_rosetta()) {
       packageStartupMessage(
         paste(
@@ -242,8 +242,9 @@ on_macos_10_13_or_lower <- function() {
 }
 
 on_rosetta <- function() {
+  # make sure to suppress warnings and ignore the stdout + stderr so that this is silent
   identical(tolower(Sys.info()[["sysname"]]), "darwin") &&
-    identical(system("sysctl -n sysctl.proc_translated", intern = TRUE), "1")
+    identical(suppressWarnings(system("sysctl -n sysctl.proc_translated", intern = TRUE, ignore.stderr = TRUE, ignore.stdout = TRUE)), "1")
 }
 
 option_use_threads <- function() {

r/tests/testthat/test-arrow-pacakge.R

@@ -0,0 +1,21 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+test_that("on_rosetta() does not warn", {
+  # There is no warning
+  expect_warning(on_rosetta(), NA)
+})