Fix modular autoinit breakage

[bcspragu]

I ran into this issue updating dependencies for a Nuxt 3 app. The problem is that process.{client,server,dev} are defined even on the client, so the client ends up broken with errors like:

Uncaught TypeError: can't access property "__FIREBASE_DEFAULTS__", process.env is undefined

Since the code only uses process.env, this updates the check to look explicitly for process.env.

Fixes #6662

[changeset-bot]

⚠️ No Changeset found

Latest commit: 57b7f53

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[hsubox76]

Thank you! Can you add a changeset for @firebase/util? Patch should be fine.

[bcspragu]

Should be all set, updated @firebase/util to 1.7.1

[hsubox76]

Thanks! Just fyi, we use changesets so instead of altering the package.json directly, you'd need to follow the directions in the "No Changeset Found" comment above.

But it turns out I also have to make other fixes in that file due to #6660 so I can just put this fix in the same PR so we won't run into any merge conflicts or anything and you don't have to worry about the changeset tool.

[hsubox76]

Rolling this fix into #6665

[bcspragu]

Sounds good to me, and sorry for glossing over the (very clearly laid out) instructions!