Make dynamic-brokers.md easier to read

[Kolaer]

I think after these changes, the article is somewhat easier to read. There are still some rough edges, but we can focus on them later.

I can go through the docs and fix everything that I can find, but it'll take some time, so let's start with some smaller changes first.

[Kolaer]

Hi, @s3rius

Please proof-read the changes. I'm not 100% sure that they are in sync with the code/examples.

[codecov-commenter]

Codecov Report

Merging #206 (d6a1726) into master (04dd68d) will increase coverage by 11.05%.
Report is 126 commits behind head on master.
The diff coverage is 73.03%.

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@@             Coverage Diff             @@
##           master     #206       +/-   ##
===========================================
+ Coverage   61.94%   72.99%   +11.05%     
===========================================
  Files          37       48       +11     
  Lines         938     1518      +580     
===========================================
+ Hits          581     1108      +527     
- Misses        357      410       +53     

Files	Coverage Δ
taskiq/__init__.py	100.00% <100.00%> (ø)
taskiq/abc/formatter.py	100.00% <100.00%> (ø)
taskiq/abc/middleware.py	100.00% <ø> (ø)
taskiq/abc/result_backend.py	100.00% <ø> (ø)
taskiq/abc/schedule_source.py	100.00% <100.00%> (ø)
taskiq/acks.py	100.00% <100.00%> (ø)
taskiq/api/__init__.py	100.00% <100.00%> (ø)
taskiq/brokers/inmemory_broker.py	96.55% <100.00%> (+34.28%)	⬆️
taskiq/cli/watcher.py	0.00% <ø> (ø)
taskiq/cli/worker/log_collector.py	100.00% <ø> (ø)
... and 31 more

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[s3rius]

It's easier to read, indeed. Thank you very much.