secure boot: In Reflashable mode, make sure the bootloader digest updates

... whenever the bootloader.bin is updated

components/bootloader/subproject/CMakeLists.txt

@@ -75,7 +75,8 @@ if(CONFIG_SECURE_BOOTLOADER_REFLASHABLE)
     add_custom_command(OUTPUT "${bootloader_digest_bin}"
         COMMAND ${CMAKE_COMMAND} -E echo "DIGEST ${bootloader_digest_bin}"
         COMMAND ${ESPSECUREPY} digest_secure_bootloader --keyfile "${secure_bootloader_key}"
-            -o "${bootloader_digest_bin}" "${CMAKE_BINARY_DIR}/bootloader.bin"
+        -o "${bootloader_digest_bin}" "${CMAKE_BINARY_DIR}/bootloader.bin"
+        MAIN_DEPENDENCY gen_project_binary
         DEPENDS gen_secure_bootloader_key gen_project_binary
         VERBATIM)