xcresult_logs.py: Fix potential UnicodeEncodeError

[dconeybe]

This PR fixes the following UnicodeDecodeError that sometimes happens in GitHub actions:

Traceback (most recent call last):
  File "scripts/xcresult_logs.py", line 300, in <module>
    main()
  File "scripts/xcresult_logs.py", line 67, in main
    sys.stdout.write(log)
UnicodeEncodeError: 'ascii' codec can't encode character u'\u2019' in position 421: ordinal not in range(128)

e.g. https://github.com/firebase/firebase-ios-sdk/runs/6000587971

#no-changelog

[paulb777]

Thanks!

[dconeybe]

Hmm, this fix didn't work. Instead, I got

Traceback (most recent call last):
  File "scripts/xcresult_logs.py", line 312, in <module>
    main()
  File "scripts/xcresult_logs.py", line 73, in main
    log_encoded = log.encode(sys.stdout.encoding, errors='backslashreplace')
TypeError: encode() argument 1 must be string, not None

https://github.com/firebase/firebase-ios-sdk/runs/6009395104

I'm going to try a different approach.

[dconeybe]

That fix didn't work either. It looks like sys.stdout doesn't have a buffer attribute. This time I got this exception:

Traceback (most recent call last):
  File "scripts/xcresult_logs.py", line 305, in <module>
    main()
  File "scripts/xcresult_logs.py", line 72, in main
    sys.stdout.buffer.write(log_encoded)
AttributeError: 'file' object has no attribute 'buffer'

e.g. https://github.com/firebase/firebase-ios-sdk/runs/6011521209

I've pushed 1b5d296 to try a different approach again.

[dconeybe]

Finally, that worked. I'm going to merge this now.

e.g. https://github.com/firebase/firebase-ios-sdk/runs/6012727534