fix: merge custom queries rather than appending

[danielroe]

Currently we simply append any existing resourceQuery to the end of any generated query string. In the event of a custom query being passed this leads to an invalid query, such as:

const scriptQuery = '?vue&type=script&lang=js?custom=true'
const templateQuery = '?vue&type=template&id=49803768?custom=true'
const styleQuery = '?vue&type=style&index=0&id=49803768&lang=css?custom=true'

The four locations where this happens are:

vue-loader/src/index.ts

Line 159 in 6dce21e

const query = `?vue&type=script${attrsQuery}${resourceQuery}`

vue-loader/src/index.ts

Line 179 in 6dce21e

const query = `?vue&type=template${idQuery}${scopedQuery}${tsQuery}${attrsQuery}${resourceQuery}`

vue-loader/src/index.ts

Line 199 in 6dce21e

const query = `?vue&type=style&index=${i}${idQuery}${inlineQuery}${attrsQuery}${resourceQuery}`

vue-loader/src/index.ts

Line 271 in 6dce21e

const query = `?vue&type=custom&index=${i}${blockTypeQuery}${issuerQuery}${attrsQuery}${resourceQuery}`

I realise this is a bit of an edge case, but as long as we are appending resourceQuery to the end of a query string we should probably normalise it.