title: Cannot replace line after string match in jenkins pipeline using variables
body: <p>I need to replace a line in a file. If the line starts with the term "url", I need to replace the value.</p>
  
  <p>file.txt --</p>
  
  <pre><code>...
  url : http://www.google.com
  ..
  </code></pre>
  
  <p>I need to change this value to 
  url : <a href="http://www.facebook.com" rel="noreferrer">http://www.facebook.com</a></p>
  
  <p>I tried the following code but it did not work -</p>
  
  <pre><code>FACEBOOK_URL = "http://www.facebook.com"
  sh("sed -i \\"s?^url.*\\$?url: ${FACEBOOK_URL}?\\" file.txt")
  </code></pre>
  
  <p>I'm using a Jenkins Pipeline. I need to replace the string using a variable.</p>