CI: don't be so chatty while looking for clang-format

ci/calamaresstyle

@@ -13,15 +13,16 @@ export LANG LC_ALL LC_NUMERIC
 
 AS=$( which astyle )
 
-for _cf in clang-format-7 clang-format-8 clang-format70 clang-format80 clang-format
+CF_VERSIONS="clang-format-7 clang-format-8 clang-format70 clang-format80 clang-format"
+for _cf in $CF_VERSIONS
 do
 	# Not an error if this particular clang-format isn't found
-	CF=$( which $_cf || true )
+	CF=$( which $_cf 2> /dev/null || true )
 	test -n "$CF" && break
 done
 
 test -n "$AS" || { echo "! No astyle found in PATH"; exit 1 ; }
-test -n "$CF" || { echo "! No clang-format-7 found in PATH"; exit 1 ; }
+test -n "$CF" || { echo "! No clang-format ($CF_VERSIONS) found in PATH"; exit 1 ; }
 test -x "$AS" || { echo "! $AS is not executable."; exit 1 ; }
 test -x "$CF" || { echo "! $CF is not executable."; exit 1 ; }