fix(db-postgres): payload.db.upsert inserts new rows instead of updating existing ones (#9916)

### What?
`payload.db.updateOne` (and so `payload.db.upsert`) with drizzle
adapters used incoming `where` incorrectly and worked properly only
either if you passed `id` or some where query path required table joins
(like `where: { 'array.title'`) which is also the reason why `upsert`
_worked_ with user preferences specifically, because we need to join the
`preferences_rels` table to query by `user.relationTo` and `user.value`

Fixes https://github.com/payloadcms/payload/issues/9915

This was found here - https://github.com/payloadcms/payload/pull/9913,
the database KV adapter uses `upsert` with `where` by unique fields.

test/database/int.spec.ts

@@ -1076,4 +1076,37 @@ describe('database', () => {
 
     expect(relationBDocs.docs).toHaveLength(0)
   })
+
+  it('should upsert', async () => {
+    const postShouldCreated = await payload.db.upsert({
+      req: {},
+      collection: 'posts',
+      data: {
+        title: 'some-title-here',
+      },
+      where: {
+        title: {
+          equals: 'some-title-here',
+        },
+      },
+    })
+
+    expect(postShouldCreated).toBeTruthy()
+
+    const postShouldUpdated = await payload.db.upsert({
+      req: {},
+      collection: 'posts',
+      data: {
+        title: 'some-title-here',
+      },
+      where: {
+        title: {
+          equals: 'some-title-here',
+        },
+      },
+    })
+
+    // Should stay the same ID
+    expect(postShouldCreated.id).toBe(postShouldUpdated.id)
+  })
 })