Fix copyright year not updated in Contexty.java

Missed in f9c34e4

Author: yawnoc

app/src/main/java/io/github/yawnoc/utilities/Contexty.java

@@ -1,5 +1,5 @@
 /*
-  Copyright 2021--2023 Conway
+  Copyright 2021--2023, 2025 Conway
   Licensed under the GNU General Public License v3.0 (GPL-3.0-only).
   This is free software with NO WARRANTY etc. etc.,
   see LICENSE or <https://www.gnu.org/licenses/>.