title: workbox webpack plugin exclude folder from precache manifest
body: <p>I'm using the workbox webpack plugin with vue cli 3 and I would like to exclude the files in a folder from being added to the precache manifest.</p>
  
  <p>See my current file structure below</p>
  
  <p>/src <br/>
    &nbsp;/assets <br/>
      &nbsp;&nbsp;/css <br/>
      &nbsp;&nbsp;/shell<br/>
      &nbsp;&nbsp;&nbsp;&nbsp;file1.svg<br/>
      &nbsp;&nbsp;&nbsp;&nbsp;file2.svg<br/>
      &nbsp;&nbsp;&nbsp;&nbsp;file3.svg<br/>
      &nbsp;&nbsp;/svg<br/>
      &nbsp;&nbsp;&nbsp;&nbsp;file4.svg<br/>
      &nbsp;&nbsp;&nbsp;&nbsp;file5.svg<br/>
      &nbsp;&nbsp;&nbsp;&nbsp;file6.svg<br/></p>
  
  <p>I want to include the files in the shell folder in my precache manifest but I don't want to include the ones in the svg folder.</p>
  
  <p>I've tried using the <b>globIgnores</b> and <b>exclude</b> options of <b>workboxOptions</b> in the <b>vue.config.js</b> file but I'm not getting the desired result. </p>
  
  <p>When I tried <code>globIgnores: ['src/assets/svg/*']</code>, nothing happened as all the files are included </p>
  
  <p>When I tried  <code>exclude: [/\.svg$/]</code>, it excluded the svg files in both folders.</p>
  
  <p>I tried to alter the match pattern for the exclude option per below but it didn't work either: </p>
  
  <pre><code>exclude: [/^file4.*\.svg$/,
            /^file5.*\.svg$/,
            /^file6.*\.svg$/]
  </code></pre>