test: make reflection_cxx.test tap-compatible

Part of #7618

NO_DOC=internal
NO_CHANGELOG=internal

test/unit/reflection_cxx.cc

+#define UNIT_TAP_COMPATIBLE 1
 #include "unit.h"
 
 #include <string.h>

test/unit/reflection_cxx.result

-1..30
-ok 1 - type.name
-ok 2 - type.parent
-ok 3 - type.parent
-ok 4 - is_instance
-ok 5 - is_instance
-ok 6 - is_instance
-ok 7 - is_instance
-ok 8 - methods order
-ok 9 - methods order
-ok 10 - methods order
-ok 11 - methods order
-ok 12 - methods order
-ok 13 - method.owner
-ok 14 - method.name
-ok 15 - method.rtype (non void)
-ok 16 - method.rtype (void)
-ok 17 - method.nargs (zero)
-ok 18 - method.nargs (non-zero)
-ok 19 - method.atype
-ok 20 - method.isconst
-ok 21 - !method.isconst
-ok 22 - !invokable<invalid args>
-ok 23 - !invokable<extra args>
-ok 24 - !invokable<>(invalid object)
-ok 25 - invokable<const char *>
-ok 26 - invokable<void, const char *>
-ok 27 - invoke (int)
-ok 28 - invoke (const char *)
-ok 29 - invoke (void)
-ok 30 - !invokable<>() on const method with non-const object