feat: Throw an InvalidRequest whenever a curl request fails

[colinodell]

Fixes #90

This is one of three possible solutions to #90. #104 is similar but doesn't use catchable exceptions, and #105 is more about avoiding the issue than notifying the user.

Checklist

• I have made a material change to the repo (functionality, testing, spelling, grammar)
• I have read the [Contribution Guide] and my PR follows them.
• I updated my branch with the master branch.
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation about the functionality in the appropriate .md file
• I have added in line documentation to the code I modified

Short description of what this PR does:

• An exception will be thrown if a curl request fails due to something like SSL verification (BC break)
• Uses composer/ca-bundle (if installed) to locate the system's CA bundle or fall back to Mozilla's (Support composer/ca-bundle fallback #105)

[SendGridDX]

All committers have signed the CLA.

[thinkingserious]

Hello @colinodell,

I like this solution combined with #105. What do you see as the cons of choosing this solution to #104?

Thanks!

With Best Regards,

Elmer

[colinodell]

Hey Elmer,

I strongly prefer this option because any issues result in thrown exceptions which can be caught and dealt with. The alternate approach in #104 cannot be caught and handled by anyone using this library, it just provides a better error message instead of failing silently.

The only potential con is that this is technically a backward-compatibility break as users of this library may not be expecting any exceptions to be thrown, so you'll probably want to bump the major version of this library if you're following semver. Despite this, I do think this approach is best way forward and it aligns with how other API libraries also throw expections when issues occur.

[thinkingserious]

Thanks @colinodell,

I agree with you. Please fold #105 into this PR. Thanks!

[colinodell]

Done! I have also added some documentation via 281048f

[thinkingserious]

Hello @colinodell,

Thanks again for the PR!

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[colinodell]

Done! Thanks for letting me know about that, I appreciate it!

[thinkingserious]

Hello @colinodell,

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[thinkingserious]

Hello @colinodell,

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[alextech]

Is this the same or conflict with what I already have done at #99 ?

[childish-sambino]

LGTM