chore(rel): spelling fix for postgres collation docs (#1173)

Quick spelling fix 

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Author: jdpleiness

docs/admin/postgresql_collation_version_mismatch_resolution.mdx

@@ -2,7 +2,7 @@
 
 # Issue Summary
 
-Customers whom initially deployed Sourcegraph versions prior to v6.2.2553 using the Sourcegraph provided PostgreSQL containers may encounter PostgreSQL collation version mismatch warnings after upgrading to more recent Sourcegraph versions due to an underlying glibc version update.
+Customers who initially deployed Sourcegraph versions prior to v6.2.2553 using the Sourcegraph provided PostgreSQL containers may encounter PostgreSQL collation version mismatch warnings after upgrading to more recent Sourcegraph versions due to an underlying glibc version update.
 
 # Impact