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_bot3/autonomous/autonomous_actor.cc b/y2023_bot3/autonomous/autonomous_actor.cc
index 7c722be..61811d7 100644
--- a/y2023_bot3/autonomous/autonomous_actor.cc
+++ b/y2023_bot3/autonomous/autonomous_actor.cc
@@ -20,8 +20,7 @@
 DEFINE_bool(one_piece, false,
             "End charged_up autonomous after first cube is placed.");
 
-namespace y2023_bot3 {
-namespace autonomous {
+namespace y2023_bot3::autonomous {
 
 using ::frc971::ProfileParametersT;
 
@@ -287,5 +286,4 @@
   }
 }
 
-}  // namespace autonomous
-}  // namespace y2023_bot3
+}  // namespace y2023_bot3::autonomous