`workbox-google-analytics` disregard payload parameters when it's a POST request

[myasul]

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Library Affected: workbox-google-analytics

Browser & Platform: Version 101.0.4951.54 (Official Build) (arm64) in macOS Monterey

Issue or Feature Request Description: When I used workbox-google-analytics to make sure all GA requests are processed regardless of network status, I noticed that the requests are not registering on the custom dimension that I made. When I checked the reprocessed requests (GA requests processed during background sync), I noticed that a lot of payload parameters are missing (see screenshot).

When I checked the codebase (packages/workbox-google-analytics/src/initialize.ts) it seems that it does disregard the URLSearchParams if the GA request is a POST request. This might be a bug?

I fixed it in our codebase using patch-package. Let me know if this is indeed a bug, I'm happy to submit a PR request!