Use gzip (.gz) instead of bzip2 (.bz2) to compress logs

[mvidner]

Problem

Quoting #1378:

GitHub does not allow attaching bzip2 files. In order to make error reporting easier, agama logs store should use a different format (e.g., .gz and .tgz are supported). Otherwise, you need to uncompress and compress the logs again before submitting them.

Solution

Use gzip and .gz instead.

Testing

• [x] Tested manually

Screenshots

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