Clean up things that include script/standard.h

Remove standard.h from files that don't use anything in it, and include
it in files that do.

src/test/script_tests.cpp

@@ -14,6 +14,7 @@
 #include <script/sigcache.h>
 #include <script/sign.h>
 #include <script/signingprovider.h>
+#include <script/standard.h>
 #include <streams.h>
 #include <test/util/json.h>
 #include <test/util/random.h>