Code Block macro: wrong formatting shown for ampersand

ih3. Summary
When using the '&' symbol in the Code Block macro, the wrong formatting is shown for ampersand.

Environment

• Confluence Cloud
• Any browser

Steps to Reproduce

• Confluence page on edit mode.
• Add the Code Block macro ({Code Block} or + icon > Other macros > Code Block).
• Add code such as this example containing an ampersand on the Code Block macro box:

   <a href="https://test.test.br/?exp_partner=TESTTEST&utm_source=TESTTEST&utm_campaign=affiliates&utm_medium=link" target="_blank">sometext</a>
  

• Publish the page.

Expected Results

• The code is shown correctly.

Actual Results

• The code appears as:

  <a href="https://test.br/?exp_partner=TEST&amp;utm_source=TEST&amp;utm_campaign=affiliates&amp;utm_medium=link" target="_blank">sometext</a>
  

Workaround

• This bug doesn't appear in the new editor. Customers impacted by this bug should use the new editor, which is currently being rolled out to all customers.