python: Open debian/changelog explicitly as UTF-8
The package build failed on the buildd hosts:
```
cd python && python3.6 setup.py test
Traceback (most recent call last):
File "setup.py", line 32, in <module>
version=get_debian_version(),
File "setup.py", line 22, in get_debian_version
head = open(changelog).readline()
File "/usr/lib/python3.6/encodings/ascii.py", line 26, in decode
return codecs.ascii_decode(input, self.errors)[0]
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc5 in position
111: ordinal not in range(128)
```
Benjamin Drung
5 years ago