docs: Update mandatory 2fa contributors 2023 to past tense (#34549)

Co-authored-by: Alex Nguyen <[email protected]>

data/reusables/two_fa/mandatory-2fa-contributors-2023-nested.md

@@ -1 +1 @@
-As of March 2023, {% data variables.product.prodname_dotcom %} began to require all users who contribute code on {% data variables.product.prodname_dotcom_the_website %} to enable one or more forms of two-factor authentication (2FA). If you were in an eligible group, you would have received a notification email when that group was selected for enrollment, marking the beginning of a 45-day 2FA enrollment period, and you would have seen banners asking you to enroll in 2FA on {% data variables.product.prodname_dotcom_the_website %}. If you didn't receive a notification, then you were not part of a group required to enable 2FA, though we strongly recommend it.
+As of March 2023, {% data variables.product.prodname_dotcom %} required all users who contribute code on {% data variables.product.prodname_dotcom_the_website %} to enable one or more forms of two-factor authentication (2FA). If you were in an eligible group, you would have received a notification email when that group was selected for enrollment, marking the beginning of a 45-day 2FA enrollment period, and you would have seen banners asking you to enroll in 2FA on {% data variables.product.prodname_dotcom_the_website %}. If you didn't receive a notification, then you were not part of a group required to enable 2FA, though we strongly recommend it.