dgit autopkgtests broken by git 2.40

Imported from Debian bug http://bugs.debian.org/1033503:

Package: dgit
Version: 10.7
Control: affects -1 git

Some of dgit's tests create strange git objects, to test error
handling. For example, to avoid a repetition of #849041.

git 2.40, just uploaded to unstable, has this change:

 | * "git hash-object" now checks that the resulting object is well
 | formed with the same code as "git fsck".
 | (merge 8e4309038f jk/hash-object-fsck later to maint).

This was probably a good idea. So, dgit's tests need to be updated.
Normally I would file this bug as RC and make the necessary changes.

However, we are currently in the freeze for bookworm. Information on
tracker.d.o suggests that git is not going to migrate to bookworm
anyway, without an unblock from the release team. I don't see an
unblock request in https://bugs.debian.org/release.debian.org .

Release team: do you think we (dgit maintainers) should update the
test suite now, for bookworm ? The changes would be limited to tests,
but the new checks in git mean we'll need to take a different approach
for some of them, which might be complex or messy.

Unhelpfully, there is also #1032826, which prevents "dgit import-dsc"
working for the current git.dsc in bookworm. I think this situation
is RC. I haven't filed a bug against src:git because I think we can
fix this just by changing the infrastructure - I'm talking to DSA
about this - but if that turns out to be impossible, we may need to
upload a no-source-changes src:git :-/.

Thanks for everyone's attention and advice/opinions.

Thanks,
Ian.

--
Ian Jackson <email address hidden> These opinions are my own.

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