Nest all namespaces

The compiler supports this now.  We can type less going forward.
No functional changes.

Signed-off-by: Stephan Pleines <pleines.stephan@gmail.com>
Change-Id: I29d6fa4f9aacc0e381f1a7637294db0392466995
diff --git a/y2023/wpilib_interface.cc b/y2023/wpilib_interface.cc
index 3bf6027..8438281 100644
--- a/y2023/wpilib_interface.cc
+++ b/y2023/wpilib_interface.cc
@@ -72,8 +72,7 @@
 namespace chrono = ::std::chrono;
 using std::make_unique;
 
-namespace y2023 {
-namespace wpilib {
+namespace y2023::wpilib {
 namespace {
 
 constexpr double kMaxBringupPower = 12.0;
@@ -1058,7 +1057,6 @@
   }
 };
 
-}  // namespace wpilib
-}  // namespace y2023
+}  // namespace y2023::wpilib
 
 AOS_ROBOT_CLASS(::y2023::wpilib::WPILibRobot);