fix(firestore, ios): fix document stream handler options.

[PJakubec]

Description

On an iOS device, using includeMetadataChanges does not work stream correct metadata events for single document snapshots.
These events are not handled correctly:

• First query execution (works correctly on first app launch [because data is not yet in cache, but any subsequent launch will be handled incorrectly])
• Regaining/Losing connection to the database

Related Issues

Fixes: #12761

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• My PR includes unit or integration tests for all changed/updated/fixed behaviors (See Contributor Guide).
• All existing and new tests are passing.
• I updated/added relevant documentation (doc comments with ///).
• The analyzer (melos run analyze) does not report any problems on my PR.
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• I signed the CLA.
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Breaking Change

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• Yes, this is a breaking change.
• No, this is not a breaking change.

[google-cla]

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[TarekkMA]

Please sign the google cla

[PJakubec]

My employer did sign the CLA yesterday and added me to the relevant google group.
Looking at the CLA Troubleshooting Page (https://opensource.google/documentation/reference/cla#troubleshoot), I guess it is waiting for Google to validate the request:

If the contributor is covered by a corporate CLA, make sure that the corporation is listed at http://linkremoved/. If it's not, it simply may not have been processed yet, which typically takes a few days.

After the request is entered in the system, the CLA is sent via DocuSign to an authorized signer at the company. Once that's signed, it's sent back to Google for validation and cross-signing.