[doc] Fixes minor typo in MIGRATION.md

[snypelife]

Please prefix all TypeScript pull-requests with [Typescript]

What

Just a one word fix on the migration doc.

Checklist

• Contains customer facing changes? Including API/behavior changes
• Did you add sufficient unit test and/or integration test coverage for this PR?
  • If not, please explain why it is not required

References

JIRA:

Test & Review

Open questions / Follow-ups

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[rayokota]

Thanks @snypelife , LGTM

[rayokota]

@snypelife , can you sign the CLA?

[snypelife]

@rayokota hey sorry, I started to but wasn't exactly comfortable with providing that much PII.

I'm okay with this being closed and re-done. I was just reading the docs and figured I'd submit a patch real quick.

Thank you for reaching so quickly though 🙏