[exporter/logging] Make knownSyncError a global var

exporter/loggingexporter/known_sync_error.go

@@ -22,20 +22,20 @@ import (
 	"syscall"
 )
 
+var knownSyncErrors = []error{
+	// sync /dev/stdout: invalid argument
+	syscall.EINVAL,
+	// sync /dev/stdout: not supported
+	syscall.ENOTSUP,
+	// sync /dev/stdout: inappropriate ioctl for device
+	syscall.ENOTTY,
+	// sync /dev/stdout: bad file descriptor
+	syscall.EBADF,
+}
+
 // knownSyncError returns true if the given error is one of the known
 // non-actionable errors returned by Sync on Linux and macOS.
 func knownSyncError(err error) bool {
-	var knownSyncErrors = []error{
-		// sync /dev/stdout: invalid argument
-		syscall.EINVAL,
-		// sync /dev/stdout: not supported
-		syscall.ENOTSUP,
-		// sync /dev/stdout: inappropriate ioctl for device
-		syscall.ENOTTY,
-		// sync /dev/stdout: bad file descriptor
-		syscall.EBADF,
-	}
-
 	for _, syncError := range knownSyncErrors {
 		if errors.Is(err, syncError) {
 			return true