Fix parameter to Remove_Series

The "n" to Remove_Series should be the number of elements to be removed
from the series, not the size of the element in bytes, as the width of
the series is sizeof(REBSER *) (See Init_Memory in m-gc.c)

It should only remove the series in question.

Author: zsx

src/core/m-gc.c

@@ -771,7 +771,7 @@ static void Mark_Series(REBSER *series, REBCNT depth);
 	sp = (REBSER **)GC_Series->data;
 	for (n = 0; n < SERIES_TAIL(GC_Series); n++) {
 		if (sp[n] == series) {
-			Remove_Series(GC_Series, n, sizeof(REBSER *));
+			Remove_Series(GC_Series, n, 1);
 			break;
 		}
 	}