feat: add non .babelrc method

[bahmutov]

• closes Add option to instrument by pushing browserify => babelify istanbul plugin #47

module.exports = (on, config) => {
  on('task', require('@cypress/code-coverage/task'))
  on('file:preprocessor', require('@cypress/code-coverage/use-browserify-istanbul'))
}

Avoids using .babelrc

[bahmutov]

🎉 This PR is included in version 1.7.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

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