feat: added data residency for eu and global regions

[tiwarishubham635]

Fixes

Added region field in sendgrid options. The default region is "global" and the default host is "api.sendgrid.com". When the region is set to "eu", the host should change to "api.eu.sendgrid.com".

Checklist

• [x] I acknowledge that all my contributions will be made under the project's license
• [x] I have made a material change to the repo (functionality, testing, spelling, grammar)
• [x] I have read the Contribution Guidelines and my PR follows them
• [x] I have titled the PR appropriately
• [x] I have updated my branch with the main branch
• [x] I have added tests that prove my fix is effective or that my feature works
• [x] I have added the necessary documentation about the functionality in the appropriate .md file
• [x] I have added inline documentation to the code I modified

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[manisha1997]

LGTM