Feature/add url to google tag manager

[thinkjrs]

From my seat it looks like two very simple changes, entirely non-breaking:

1. Update GTMParams type:

In the /packages/third-parties/src/types/google.ts file add an optional url parameter to GTMParams.

export type GTMParams = {
  gtmId: string
  dataLayer?: string[]
  dataLayerName?: string
  auth?: string
  preview?: string
  url?: string // new
}

2. Update the /packages/third-parties/src/google/gtm.tsx file add the url parameter only if it is included:

  const { gtmId, dataLayerName = 'dataLayer', auth, preview, dataLayer, url } = props
  const gtmLayer = dataLayerName !== 'dataLayer' ? `&l=${dataLayerName}` : ''
  const gtmAuth = auth ? `&gtm_auth=${auth}` : ''
  const gtmPreview = preview ? `&gtm_preview=${preview}&gtm_cookies_win=x` : ''
  const gtmUrl = url ? url : 'https://www.googletagmanager.com' // new

// second script component returned now uses gtmUrl which defaults to exactly the same url as was hardcoded before
      <Script
        id="_next-gtm"
        data-ntpc="GTM"
        src={`${gtmUrl}/gtm.js?id=${gtmId}${gtmLayer}${gtmAuth}${gtmPreview}`}
      />