chore(rel): add to backup warning on postgres EOL notice (#831)

Add more clarification to the reasoning behind the suggested Postgres
backup

Author: jdpleiness

docs/admin/postgres12_end_of_life_notice.mdx

@@ -14,7 +14,7 @@ The impact to you depends on how you currently manage your Sourcegraph databases
 ### Built-in Databases
 If you are using Sourcegraph's released Postgres images, these images will be updated to Postgres 16 as part of the Sourcegraph 5.10 release (expected for November 25th, 2024) and all near term subsequent releases. With this update, Sourcegraph will experience a longer-than-average downtime at the time of the upgrade to version 5.10 or beyond. This downtime is proportional to the amount of code indexed in your instance, and can range from approximately 15 minutes to a couple of hours. The downtime will only occur at the first upgrade to version 5.10 or beyond, and not during any subsequent upgrades. 
 
-We strongly recommend that you consider this downtime prior to upgrading to ensure minimal disruption to your users. We also strongly recommend creating a backup of your database before the upgrade process.
+We strongly recommend that you consider this downtime prior to upgrading to ensure minimal disruption to your users. We also strongly recommend creating a backup of your database before the upgrade process, as an interruption to the upgrade process could lead to database corruption.
 
 ### External Databases
 If you are using externally managed databases for your Sourcegraph instance, you will need to manually upgrade the version of Postgres you are using to Postgres 16. For the Sourcegraph version that will be released on January 15, 2025 and subsequent versions, Sourcegraph will no longer run on any version of Postgres lower than Postgres 16, and you will not be able to upgrade your instance to any of those Sourcegraph versions unless that minimum required version of Postgres is met.
@@ -42,4 +42,4 @@ We expect the downtime to last approximately 2.5 hours per TB of code indexed in
 ### If I'm using external databases with Sourcegraph, how do I upgrade my version of Postgres? Can I upgrade Postgres independently of a Sourcegraph upgrade?
 Upgrading your Postgres version is highly dependent on your specific situation. If you have a separate team managing this database, reach out to them to understand their practices. And, as always, feel free to reach out to Sourcegraph to assist you.
 
-When using external databases, you can upgrade your Postgres version at any time, either alongside a Sourcegraph upgrade or independently of it. We encourage you to do so as soon as it's convenient for you.
+When using external databases, you can upgrade your Postgres version at any time, either alongside a Sourcegraph upgrade or independently of it. We encourage you to do so as soon as it's convenient for you.