title: Unhandled rejection error: invalid config key requested when attempting to update Cypress via NPM
body: <p>I am trying to update Cypress to the latest version using the following provided command:</p>
  
  <pre><code>npm install --save-dev cypress@3.2.0
  </code></pre>
  
  <p>In previous versions this has worked fine with no errors. Now, when I run this, I keep getting the following error:</p>
  
  <pre><code>Unhandled rejection Error: invalid config key requested: agentn 099cbf610e4ce787
      at BadKeyError (/usr/local/lib/node_modules/npm/node_modules/figgy-pudding/index.js:93:23)
      at pudGet (/usr/local/lib/node_modules/npm/node_modules/figgy-pudding/index.js:101:5)
      at FiggyPudding.get (/usr/local/lib/node_modules/npm/node_modules/figgy-pudding/index.js:27:12)
      at Object.get (/usr/local/lib/node_modules/npm/node_modules/figgy-pudding/index.js:159:16)
      at new PacoteOptions (/usr/local/lib/node_modules/npm/node_modules/pacote/lib/util/opt-check.js:9:21)
      at optCheck (/usr/local/lib/node_modules/npm/node_modules/pacote/lib/util/opt-check.js:63:10)
      at Object.manifest (/usr/local/lib/node_modules/npm/node_modules/pacote/manifest.js:11:10)
      at fetchPackageMetadata (/usr/local/lib/node_modules/npm/lib/fetch-package-metadata.js:58:10)
      at limited (/usr/local/lib/node_modules/npm/node_modules/call-limit/call-limit.js:29:10)
      at /usr/local/lib/node_modules/npm/lib/install/deps.js:235:14
      at /usr/local/lib/node_modules/npm/node_modules/slide/lib/async-map.js:52:35
      at Array.forEach (&lt;anonymous&gt;)
      at /usr/local/lib/node_modules/npm/node_modules/slide/lib/async-map.js:52:11
      at Array.forEach (&lt;anonymous&gt;)
      at asyncMap (/usr/local/lib/node_modules/npm/node_modules/slide/lib/async-map.js:51:8)
      at exports.getAllMetadata (/usr/local/lib/node_modules/npm/lib/install/deps.js:206:3)
  
  npm ERR! cb() never called!
  
  npm ERR! This is an error with npm itself. Please report this error at:
  npm ERR!     &lt;https://npm.community&gt;
  
  npm ERR! A complete log of this run can be found in:
  npm ERR!     /Users/jaswindersingh/.npm/_logs/2019-03-15T13_32_13_190Z-debug.log
  </code></pre>
  
  <p>Could anyone point me to what this means and how I can fix it? 
  Never seen this kind of error before? </p>
  
  <p>And as far as I know I've not made any changes to any of my packages in either <code>package.json</code> or <code>package-lock.json</code> etc (from what I have read so far from similar posts)</p>