Set VALID_END_DATE via the port Makefile. This would otherwise only be set
if the CMake argument ENABLE_BANKDATA_DOWNLOAD is true, but we cannot download
files during the build process. This value needs to be defined as the last day
the bank data is valid in %d.%m.%Y format to enable the custom commands/targets
that build that databases.

--- src/CMakeLists.txt.orig	2025-05-15 11:18:20 UTC
+++ src/CMakeLists.txt
@@ -40,7 +40,7 @@ message(STATUS "Using bank data db ${BANKDATA_TEST_DBP
 message(STATUS "Using bank data db ${BANKDATA_CH_DBPATH}")
 message(STATUS "Using bank data db ${BANKDATA_TEST_DBPATH}")
 
-set(VALID_END_DATE "")
+set(VALID_END_DATE "%%BANKDATA_END_DATE%%")
 
 if(ENABLE_BANKDATA_DOWNLOAD)
     extract_date(