title: Gradle "Entry .classpath is a duplicate but no duplicate handling strategy has been set"
body: <p>I'm trying to build a gradle project but, when I try <code>$ gradle build</code> I get the following output:</p>
  <pre><code>Starting a Gradle Daemon (subsequent builds will be faster)
  &gt; Task :jar FAILED
  
  FAILURE: Build failed with an exception.
  
  * What went wrong:
  Execution failed for task ':jar'.
  &gt; Entry .classpath is a duplicate but no duplicate handling strategy has been set. Please refer to https://docs.gradle.org/7.0/dsl/org.gradle.api.file.CopySpec.html#org.gradle.api.file.CopySpec:duplicatesStrategy for details.
  
  * Try:
  Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
  
  * Get more help at https://help.gradle.org
  
  BUILD FAILED in 11s
  4 actionable tasks: 2 executed, 2 up-to-date
  </code></pre>
  <p>After doing <code>Get-ChildItem -Path ./ -Filter .classpath -Recurse -Force</code> I concluded that
  I don't even have a single file named <code>.classpath</code> in my project. What do I do?</p>