test/raw: Re-enable span tests

This got broken by the c++20 conversion.

Change-Id: I8632633c68474d63a8e4287b8a0b2a688d7bda4e
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/test/raw.cpp b/test/raw.cpp
index 7da5acb..5e48419 100644
--- a/test/raw.cpp
+++ b/test/raw.cpp
@@ -5,6 +5,7 @@
 #include <catch2/catch_test_macros.hpp>
 #endif
 #include <endian.h>
+#include <span>
 #include <stdexcept>
 #include <stdplus/raw.hpp>
 #include <string_view>
@@ -160,7 +161,6 @@
     CHECK(s[1] == sv[1]);
 }
 
-#ifdef STDPLUS_SPAN_TYPE
 TEST_CASE("Span Extract TooSmall", "[Extract]")
 {
     const std::vector<char> v = {'c'};
@@ -274,8 +274,6 @@
     CHECK(s2[1] == arr[1]);
 }
 
-#endif
-
 } // namespace
 } // namespace raw
 } // namespace stdplus