Bump debian from bookworm-20250908 to bookworm-20250929 in /.github/docker (#2045)

Bumps debian from bookworm-20250908 to bookworm-20250929.


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Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/docker/Dockerfile.debian

@@ -1,3 +1,3 @@
-FROM debian:bookworm-20250908
+FROM debian:bookworm-20250929
 
 CMD echo this is a dummy file used to automate dependency upgrades for plugins