Remove sh usages

[felixfontein]

Needs to be rebased/updated once #120 has been merged.

[felixfontein]

@gotmax23 the failing tests show a problem with ansible_core.subprocess_util.async_log_run: if a single line is too large of the output (in this case stdout), asyncio.streams dies:

[...]
  File "/opt/hostedtoolcache/Python/3.11.2/x64/lib/python3.11/site-packages/antsibull_core/subprocess_util.py", line 40, in _stream_log
    line = await stream.readline()
           ^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/hostedtoolcache/Python/3.11.2/x64/lib/python3.11/asyncio/streams.py", line 554, in readline
    raise ValueError(e.args[0])
ValueError: Separator is found, but chunk is longer than limit

This requires a very large output, which apparently happens for ansible-doc --metadata-dump --no-fail-on-errors when the ansible package is installed. For the 8.0.0 build I did recently, the maximum line length I found was 68115.

According to the asyncio/streams.py in Python 3.10, the default limit is 65536 bytes for a line. This can be adjusted by passing limit=HIGHER_LIMIT to asyncio.create_subprocess_exec(), but IMO this is only a band-aid, since there is no value for "unlimited". We might have to implement line parsing ourselves?

[felixfontein]

I've tried it out in ansible-community/antsibull-core#53, it seems to work well.

[felixfontein]

Restarting tests now that ansible-community/antsibull-core#53 has been merged.

[felixfontein]

(Rebased to remove conflict.)

[gotmax23]

Thanks for working on this! I'll take a closer look later today or tomorrow.

[gotmax23]

This PR is pretty straightfoward; I just have a couple comments 😄.

[gotmax23]

Ack. Let's do this 🎉!

[felixfontein]

@gotmax23 thanks for preparing this and reviewing!