title: how to use git log to return pull-request number between tags
body: <p>I tried to use git log ocmmand to retrieve all pull-request between two tags. However for some reason, one of hash does not contains PR issume number? What command I should use instead? I have tried. but same result return</p>
  
  <pre><code>/User$git log tag1..tag2 --pretty=oneline --date=short -- .
  /User$git log tag1..tag2 --pretty=format:%h%an%s %cd --date=short -- .
  </code></pre>
  
  <pre><code>hash1 (tag: tagabc) PR header (#17854)
  hash2 (tag: tagabc2) PR header2
  hash3 (tag: tagabc3) PR header3(#17932)
  </code></pre>