[libcxx] [test] Strip trailing whitespace. NFC.

llvm-svn: 346826
diff --git a/libcxx/test/std/containers/views/span.cons/container.pass.cpp b/libcxx/test/std/containers/views/span.cons/container.pass.cpp
index 478a3da..401f41e 100644
--- a/libcxx/test/std/containers/views/span.cons/container.pass.cpp
+++ b/libcxx/test/std/containers/views/span.cons/container.pass.cpp
@@ -7,7 +7,7 @@
 // Source Licenses. See LICENSE.TXT for details.
 //
 //===---------------------------------------------------------------------===//
-// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17 
+// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
 
 // <span>