Update copyright year

configure.ac.in

 dnl
-dnl Copyright (c) 2004-2022 The Xfce development team
+dnl Copyright (c) 2004-2023 The Xfce development team
 dnl
 dnl 2005-2007 Jasper Huijsmans <jasper@xfce.org>
 dnl 2006-2008 Nick Schermer <nick@xfce.org>
@@ -27,7 +27,7 @@ m4_define([panel_debug_default], [ifelse(xfce4_panel_version_tag(), [git], [yes]
 dnl ***************************
 dnl *** Initialize autoconf ***
 dnl ***************************
-AC_COPYRIGHT([Copyright (c) 2004-2022
+AC_COPYRIGHT([Copyright (c) 2004-2023
         The Xfce development team. All rights reserved.
 
 Written for Xfce by Jasper Huijsmans <jasper@xfce.org>

docs/reference/libxfce4panel-docs.xml

@@ -16,7 +16,7 @@
       <ulink role="online-location" url="https://developer.xfce.org/&package_name;/index.html">https://developer.xfce.org/&package_name;/</ulink>.
     </releaseinfo>
     <copyright>
-      <year>2022</year>
+      <year>2023</year>
       <holder>The Xfce development team</holder>
     </copyright>
   </bookinfo>

panel/main.c

@@ -295,7 +295,7 @@ main (gint argc, gchar **argv)
       else
         g_print ("%s", PACKAGE_NAME);
       g_print (" %s (Xfce %s)\n\n", PACKAGE_VERSION, xfce_version_string ());
-      g_print ("%s\n", "Copyright (c) 2004-2022");
+      g_print ("%s\n", "Copyright (c) 2004-2023");
       g_print ("\t%s\n\n", _("The Xfce development team. All rights reserved."));
       g_print (_("Please report bugs to <%s>."), PACKAGE_BUGREPORT);
       g_print ("\n");

panel/panel-dialogs.c

@@ -82,7 +82,7 @@ panel_dialogs_show_about (void)
   gtk_about_dialog_set_authors (GTK_ABOUT_DIALOG (about_dialog), (const gchar**) authors);
   g_strfreev (authors);
   gtk_about_dialog_set_comments (GTK_ABOUT_DIALOG (about_dialog), _("The panel of the Xfce Desktop Environment"));
-  gtk_about_dialog_set_copyright (GTK_ABOUT_DIALOG (about_dialog), "Copyright \302\251 2004-2022 The Xfce development team");
+  gtk_about_dialog_set_copyright (GTK_ABOUT_DIALOG (about_dialog), "Copyright \302\251 2004-2023 The Xfce development team");
   gtk_about_dialog_set_license (GTK_ABOUT_DIALOG (about_dialog), XFCE_LICENSE_GPL);
   gtk_about_dialog_set_program_name (GTK_ABOUT_DIALOG (about_dialog), PACKAGE_NAME);
   gtk_about_dialog_set_translator_credits (GTK_ABOUT_DIALOG (about_dialog), _("translator-credits"));