title: How can i hide a token in the firebase function?
body: <p>i have created subscription form on my gatsby website.</p>
  <p>I wanted sent request to activeCampaign with contact data but i couldn't due to cors policy. So I have created firebase function to which i sent data from form and in headers api  active campaign token. Everything works but when i  go to on my firebase function adress i see activeCampaign token in website.</p>
  <p>So if someone gets the address of my firebase function, they will also get an api token for the active campaign. How can I hide this token?</p>