use memmove() in appropriate places

src/http/ngx_http_script.c

diff --git a/src/http/ngx_http_script.c b/src/http/ngx_http_script.c
index ef69155..8b861ce 100644
--- a/src/http/ngx_http_script.c
+++ b/src/http/ngx_http_script.c
@@ -1089,7 +1089,7 @@
                          NGX_UNESCAPE_REDIRECT);
 
         if (src < e->pos) {
-            dst = ngx_copy(dst, src, e->pos - src);
+            dst = ngx_movemem(dst, src, e->pos - src);
         }
 
         e->pos = dst;