use retry mode: standard

[robpickerill]

This PR moves the boto config to using retry mode: standard, as the default retry mode is legacy.
https://boto3.amazonaws.com/v1/documentation/api/latest/guide/retries.html

Please let me know your thoughts on this PR.

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[codecov-commenter]

Codecov Report

Merging #537 (2461439) into develop (c63dfaf) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##           develop      #537   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           42        42           
  Lines         3026      3030    +4     
  Branches       455       455           
=========================================
+ Hits          3026      3030    +4     

Impacted Files	Coverage Δ
awslimitchecker/connectable.py	100.00% <100.00%> (ø)

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[jantman]

@robpickerill I'm going to hold off on merging this one for now. I have some questions about the changes, but more importantly, I've also become a fan of the "adaptive" retry mode, and think that one might be a better option...

Also, a nitpick: I'm not in favor of bumping up the max line length. PEP8 clearly says to limit it to 79 characters. I... either find that too antiquated or don't like odd numbers, take your pick... but I don't really want to bump it up by an arbitrary 5 characters for one PR. To be fair (and pedantic?) I also use an editor that's set up to show two 80-character files side by side.

[robpickerill]

Hey, would you prefer adaptive? I can change that over if so

Your right on the line length, actually not sure why that's in there now I look at it - I can revisit it if you want adaptive

[jantman]

Yeah, if you don't mind, I think I'd prefer adaptive. We've been using it for some internal projects at work on very busy accounts, and it seems to work quite well.

[jantman]

This has been released in 12.0.0, which is now live on PyPI and Docker Hub. Thank you so much, and apologies for the delay!