title: Jenkins string parameter return each character after collect and join
body: <p>In my Jenkins job I return a string parameter such as that:</p>
  <pre><code>capacity/pool_capacity.suite capacity/volume_capacity.suite
  </code></pre>
  <p>In a Groovy script I use collect and join in order to add a prefix and join each string:</p>
  <pre><code>suite_file_name = suite_file_name.collect{ &quot;-f suites/$it&quot; }.join(&quot; &quot;)
  </code></pre>
  <p>In the actual output, I get the prefix for each character in the string that I return from Jenkins:</p>
  <pre><code>-f suites/c -f suites/a -f suites/p -f suites/a -f suites/c -f suites/i -f suites/t -f suites/y -f suites// -f suites/p -f suites/o -f suites/o -f suites/l -f suites/_ -f suites/c -f suites/a -f suites/p -f suites/a -f suites/c -f suites/i -f suites/t -f suites/y -f suites/. -f suites/s -f suites/u -f suites/i -f suites/t -f suites/e -f suites/  -f suites/c -f suites/a -f suites/p -f suites/a -f suites/c -f suites/i -f suites/t -f suites/y -f suites// -f suites/v -f suites/o -f suites/l -f suites/u -f suites/m -f suites/e -f suites/_ -f suites/c -f suites/a -f suites/p -f suites/a -f suites/c -f suites/i -f suites/t -f suites/y -f suites/. -f suites/s -f suites/u -f suites/i -f suites/t -f suites/e
  </code></pre>
  <p>Eventually, I want to have an output such as that:</p>
  <pre><code>-f suites/capacity/pool_capacity.suite -f suites/capacity/volume_capacity.suite
  </code></pre>
  <p>What am I doing wrong?</p>