title: UpdateMany, Upsert does not perform insert, but does update
body: <p>I am curious if there is some syntax that I am missing here:</p>
  <pre><code>db.staging_collection.updateMany(
     { &quot;account_number&quot;:&quot;288 - 1&quot;},
     { $set: { &quot;claim_diagnosis.$[element].diagnosis_code&quot; : '200' ,&quot;payers.$[pyr].payer_name&quot; : 'Self Pay'} },
     { arrayFilters: [ { &quot;element.diagnosis_code&quot;: {&quot;$eq&quot;:'2'} },{ &quot;pyr.payer_name&quot;: {&quot;$eq&quot;:'name'} } ] ,upsert: true}
  )
  </code></pre>
  <p>We've noticed that this will indeed update, but it will not insert.  Do we need a $setOnInsert or some other condition?  Any input would be great!</p>