Passing raw HTML to a slot mounting option breaks when starting with a carriage return

[lmiller1990]

Odd error with this:

const ComponentWithSlots = {
  template: `
    <div class="scoped">
      <slot name="scoped" v-bind="{ msg }" />
    </div>
  `,
  data() {
    return {
      msg: 'world'
    }
  }
}

test('scoped slots', () => {
  const wrapper = mount(ComponentWithSlots, {
    slots: {
      scoped: `
        <template #scoped="params">
        Hello {{ params.msg }}
        </template>
      `
    }
  })

  expect(wrapper.html()).toContain('Hello world')
})

Specifically:

BAD:

 scoped: `
        <template #scoped="params">
        Hello {{ params.msg }}
        </template>
      `

GOOD:

 scoped: `<template #scoped="params">
        Hello {{ params.msg }}
        </template>
      `

Probably just need to do trim.