Nest some more namespaces

Did someone previously suggest that all namespace had been
nested?  Silly.

Signed-off-by: Stephan Pleines <pleines.stephan@gmail.com>
Change-Id: I22278c1caaeba8b47dc46fb2ed3078c20a11e190
diff --git a/y2019/jevois/uart.h b/y2019/jevois/uart.h
index d3eebee..7bacbd1 100644
--- a/y2019/jevois/uart.h
+++ b/y2019/jevois/uart.h
@@ -12,8 +12,7 @@
 // This file manages serializing and deserializing the various structures for
 // transport via UART.
 
-namespace frc971 {
-namespace jevois {
+namespace frc971::jevois {
 
 constexpr size_t uart_to_teensy_size() {
   return 1 /* number of targets */ +
@@ -38,7 +37,6 @@
 std::optional<CameraCalibration> UartUnpackToCamera(
     absl::Span<const char> buffer);
 
-}  // namespace jevois
-}  // namespace frc971
+}  // namespace frc971::jevois
 
 #endif  // Y2019_JEVOIS_UART_H_