feat: add runtime config support for swUrl

[BobbieGoede]

My attempt at fixing my issue described in #72

This makes it possible to change the swUrl and add query parameters by setting it in runtimeConfig like so:

runtimeConfig: {
    pwa: {
        workbox: {
            swUrl: `/sw.js?${queryParams}`
        }
    }
}

This may not be an optimal solution but it works, please let me know if a different approach is preferred.

[kevinmarrec]

Hi @BobbieGoede , thanks for the PR ! I'll have the review done soon, sorry for the delay.

[kevinmarrec]

Closing following #72