Debian packaging: Accept *.tar.gz files as well, bump test timeouts

[martinpitt]

Upstream version 3.0.1 dropped custom release artifacts and just relies
on the automatic git archive tarballs.

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This unbreaks automated "new upstream release" notification/watching on https://tracker.debian.org/pkg/sscg

[packit-as-a-service]

Congratulations! One of the builds has completed. 🍾

You can install the built RPMs by following these steps:

• sudo yum install -y dnf-plugins-core on RHEL 8
• sudo dnf install -y dnf-plugins-core on Fedora
• dnf copr enable packit/sgallagher-sscg-48
• And now you can install the packages.

Please note that the RPMs should be used only in a testing environment.

[martinpitt]

I just packaged 3.0.1 for Debian, and it fails to build on several architectures due to test timeouts. Until 3.0.0 I used meson test --timeout-multiplier=50 -- that high value was for named_dhparams_test and I bumped the timeout in commit 2c79f05. But seems other tests need to be bumped as well, I'll add another commit for that here.