configure: bump the AC_COPYRIGHT year range
diff --git a/configure.ac b/configure.ac
index 6feab92..d08553b 100755
--- a/configure.ac
+++ b/configure.ac
@@ -31,7 +31,7 @@
 CURL_OVERRIDE_AUTOCONF
 
 dnl configure script copyright
-AC_COPYRIGHT([Copyright (c) 1998 - 2019 Daniel Stenberg, <daniel@haxx.se>
+AC_COPYRIGHT([Copyright (c) 1998 - 2020 Daniel Stenberg, <daniel@haxx.se>
 This configure script may be copied, distributed and modified under the
 terms of the curl license; see COPYING for more details])