fix(config): respect api_server.workers

[judahrand]

What does this PR address?

bentoml serve . --production was ignoring api_server.workers in bento_configuration.yaml. This is now fixed. I believe I've maintained the previous behaviour when the value was not manually set by the user.

Fixes #(issue)

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[codecov]

Codecov Report

Merging #3049 (3453280) into main (926b613) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #3049      +/-   ##
==========================================
+ Coverage   67.96%   67.97%   +0.01%     
==========================================
  Files         113      113              
  Lines       10887    10888       +1     
  Branches     1908     1921      +13     
==========================================
+ Hits         7399     7401       +2     
  Misses       3047     3047              
+ Partials      441      440       -1     

Impacted Files	Coverage Δ
bentoml/_internal/configuration/containers.py	72.94% <100.00%> (+0.50%)	⬆️

[sauyon]

One very minor nit, but otherwise looks great, thank you!

[aarnphm]

Thanks for fixing this

[ssheng]

Great catch and very lean fix. Thanks, @judahrand.

[aarnphm]

I will make a follow up PR to address some pylint issue.