refactor: use email validator instead of regex

[koladilip]

What are the changes introduced in this PR?

regexps are hard to understand so better leave that functionality to a library widely used than managing on our own.
I found some problems with customer.io validations so fixed the same also.

What is the related Linear task?

Resolves INT-3144

Please explain the objectives of your changes below

Put down any required details on the broader aspect of your changes. If there are any dependent changes, mandatorily mention them here

Any changes to existing capabilities/behaviour, mention the reason & what are the changes ?

N/A

Any new dependencies introduced with this change?

N/A

Any new generic utility introduced or modified. Please explain the changes.

N/A

Any technical or performance related pointers to consider with the change?

N/A

@coderabbitai review

---

Developer checklist

• My code follows the style guidelines of this project

• No breaking changes are being introduced.

• All related docs linked with the PR?

• All changes manually tested?

• Any documentation changes needed with this change?

• Is the PR limited to 10 file changes?

• Is the PR limited to one linear task?

• Are relevant unit and component test-cases added in new readability format?

Reviewer checklist

• Is the type of change in the PR title appropriate as per the changes?

• Verified that there are no credentials or confidential data exposed with the changes.

[codecov]

Codecov Report

Attention: Patch coverage is 91.66667% with 1 line in your changes missing coverage. Please review.

Project coverage is 90.77%. Comparing base (eacfdf1) to head (7eab840).
Report is 7 commits behind head on develop.

Files with missing lines	Patch %	Lines
src/v0/destinations/customerio/util.js	83.33%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #3985   +/-   ##
========================================
  Coverage    90.77%   90.77%           
========================================
  Files          624      624           
  Lines        32551    32552    +1     
  Branches      7726     7726           
========================================
+ Hits         29547    29548    +1     
- Misses        2748     2780   +32     
+ Partials       256      224   -32     

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[devops-github-rudderstack]

Allure Test reports for this run are available at:

• Allure Report: https://rudderlabs.github.io/rudder-transformer/80/index.html

[devops-github-rudderstack]

Allure Test reports for this run are available at:

• Allure Report: https://rudderlabs.github.io/rudder-transformer/85/index.html

[devops-github-rudderstack]

Allure Test reports for this run are available at:

• Allure Report: https://rudderlabs.github.io/rudder-transformer/87/index.html

[devops-github-rudderstack]

Allure Test reports for this run are available at:

• Allure Report: https://rudderlabs.github.io/rudder-transformer/95/index.html

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
93.8% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud