Provide utf-8 as encoding explicitly when opening text files

[rshest]

When opening text files in few places, the code relies on system default encoding being set to UTF-8.

This is safe enough in general, but there are certain corner cases like #379, where default one is e.g. ASCII (for whatever reason).

The pull request changes code to use UTF-8 encoding explicitly, without relying on the system defaults.

EDIT: There is another commit fixing a unit test (test_asm_display_group_limit), since that was failing the build, coming from master rebase.

EDIT2: The "reduced" code coverage is because of added import statements - so this is a false positive in fact.

[SendGridDX]

All committers have signed the CLA.

[codecov-io]

Codecov Report

Merging #414 into master will decrease coverage by 0.15%.
The diff coverage is 80%.

@@            Coverage Diff             @@
##           master     #414      +/-   ##
==========================================
- Coverage   88.41%   88.26%   -0.16%     
==========================================
  Files          30       30              
  Lines         924      929       +5     
  Branches      110      112       +2     
==========================================
+ Hits          817      820       +3     
  Misses         53       53              
- Partials       54       56       +2

Impacted Files	Coverage Δ
sendgrid/helpers/inbound/send.py	93.75% <100%> (+0.2%)	⬆️
sendgrid/helpers/mail/asm.py	84% <66.66%> (-6.48%)	⬇️

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[gabrielkrell]

Looks good. You can also do from io import open to make the eventual move to Python 3 (where regular open has an encoding parameter) a little easier (source).

[rshest]

Good point, thanks. Done :)

[mbernier]

@rshest

We have not been able to merge your Pull Request, but because you are awesome - we wanted to make sure you could still get a SendGrid Hacktoberfest shirt.

Please go fill out our swag form before Nov 5th and we will send the shirt! (We know that you might have tried this before and it didn’t work, sorry about that!)

You have till Nov 5th to fill out this form in order to get the Hacktoberfest shirt!

Thank you for contributing during Hacktoberfest! We hope to see you in the repos soon! Just so you know, we always give away a SendGrid shirt for your first ever non-Hacktoberfest PR that gets merged.

[thinkingserious]

Hello @rshest,

Thanks again for the PR!

We appreciate your contribution and look forward to continued collaboration. Thanks!

Team SendGrid DX