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).

wpimath/src/main/native/cpp/jni/WPIMathJNI.cpp

@@ -26,8 +26,9 @@ bool check_stabilizable(const Eigen::Ref<const Eigen::MatrixXd>& A,
   for (int i = 0; i < n; i++) {
     if (es.eigenvalues()[i].real() * es.eigenvalues()[i].real() +
             es.eigenvalues()[i].imag() * es.eigenvalues()[i].imag() <
-        1)
+        1) {
       continue;
+    }
 
     Eigen::MatrixXcd E(n, n + m);
     E << es.eigenvalues()[i] * Eigen::MatrixXcd::Identity(n, n) - A, B;