Add missing space before comment.

runtime/cpp/test/emboss_constant_view_test.cc

diff --git a/runtime/cpp/test/emboss_constant_view_test.cc b/runtime/cpp/test/emboss_constant_view_test.cc
index edbcb00..2ebf121 100644
--- a/runtime/cpp/test/emboss_constant_view_test.cc
+++ b/runtime/cpp/test/emboss_constant_view_test.cc
@@ -24,7 +24,7 @@
   EXPECT_EQ(7, MaybeConstantView</**/ ::std::uint8_t>(7).Read());
 #if EMBOSS_CHECK_ABORTS
   EXPECT_DEATH(MaybeConstantView</**/ ::std::uint8_t>().Read(), "Known\\(\\)");
-#endif // EMBOSS_CHECK_ABORTS
+#endif  // EMBOSS_CHECK_ABORTS
 }
 
 TEST(MaybeConstantViewTest, UncheckedRead) {