Move check on changes to summarize before the check on the targeted distribution

When a changelog has the message "PLEASE SUMMARIZE", it also has UNRELEASED for tageted distribution that means it triggers the previous checks and the message saying:

🛑 debian/changelog says PLEASE SUMMARIZE
Add a summary of the remaining downstream changes

is never displayed, so move it first to get a more accurate error message.

Fix: f5901ebe

Signed-off-by: Dylan Aïssi dylan.aissi@collabora.com