update vector similarity search guide

Author: mitchwadair

src/content/docs/guides/_map.json

@@ -13,7 +13,7 @@
   ["empty-array-default-value", "Empty array as a default value"],
   ["update-many-with-different-value", "Update many with different value for each row"],
   ["unique-case-insensitive-email", "Unique and Case-Insensitive Email Handling"],
-  ["vector-similarity-search", "Vector similarity search with pgvector extension"],
+  ["vector-similarity-search", "Vector similarity search"],
   ["postgresql-full-text-search", "PostgreSQL full-text search"],
   ["d1-http-with-drizzle-kit", "Cloudflare D1 HTTP API with Drizzle Kit"],
   ["point-datatype-psql", "Point datatype in PostgreSQL"],