gbp import-orig --uscan: tar -t -a -f returns exit status 2

[Nico Schlömer <nico.schloemer@gmail.com>]

Hi everyone,

I'm trying to update a package via
```
gbp import-orig --uscan
```
Unfortunately, I only get
```
uscan: error: tar -t -a -f ../gmsh-4.5.2-source.tgz subprocess
returned exit status 2
```
I can confirm that this `tar` like gives the error
```
[...]
gmsh-4.5.2-source/.clang-format
tar: Unexpected EOF in archive
tar: Error is not recoverable: exiting now
```
Curiously, when I tar from another location (same file, same md5sum),
```
tar -t -a -f /tmp/gmsh-4.5.2-source.tgz
```
it's all going fine.

Any idea what could be the issue here?

Cheers,
Nico