feat(isEmail) extend to enable allow_underscores in domain

[guspower]

Allow successful validation of email addresses containing domains with underscores

Add allow_underscores option to isEmail, pass through value to isFQDN validator.

An example underscore domain in the wild for reference

Checklist

• PR contains only changes related; no stray files, etc.
• README updated (where applicable)
• Tests written (where applicable)
• References provided in PR (where applicable) (N/A)

[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (9ba1735) 99.95% compared to head (0904c28) 99.95%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2229   +/-   ##
=======================================
  Coverage   99.95%   99.95%           
=======================================
  Files         107      107           
  Lines        2405     2405           
  Branches      604      604           
=======================================
  Hits         2404     2404           
  Partials        1        1           

Impacted Files	Coverage Δ
src/lib/isEmail.js	100.00% <100.00%> (ø)

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[guspower]

thanks for the review @WikiRik +1

[krichards]

This would be really helpful.

[guspower]

thanks for the review @rubiin +1

[profnandaa]

Thanks for the PR. LGTM.

[zhaoge068]

害