Add braces to C++ single-line loops and conditionals (NFC) (#2973)

This makes code easier to read and more consistent between C++ and Java.
Also update clang-format settings to always add a line break (even if no braces are used).

wpilibNewCommands/src/main/native/cpp/frc2/command/SequentialCommandGroup.cpp

@@ -20,7 +20,9 @@ void SequentialCommandGroup::Initialize() {
 }
 
 void SequentialCommandGroup::Execute() {
-  if (m_commands.empty()) return;
+  if (m_commands.empty()) {
+    return;
+  }
 
   auto& currentCommand = m_commands[m_currentCommandIndex];