(DOCSP-35099): Flutter: fix failing unit tests

[dacharyc]

Pull Request Info

Jira ticket: https://jira.mongodb.org/browse/DOCSP-35099

The remaining failing test is in manage_sync_session_test.dart, which Kyle modified and may have fixed in #3122 ?

Release Notes

• Flutter SDK
  • Internal: Fix failing code example tests related to SDK changes.

Review Guidelines

REVIEWING.md

[github-actions]

Readability for Commit Hash: edf7d2e

You can see any previous Readability scores (if they exist) by looking
at the comment's history.

Readability scores for changed documents:

• source/sdk/flutter/sync/write-to-synced-realm: Grade Level: 11.3, Reading Ease: 50.67

For Grade Level, aim for 8 or below.

For Reading Ease scores, aim for 60 or above:

Score	Difficulty
90-100	Very Easy
80-89	Easy
70-79	Fairly Easy
60-69	Medium
50-59	Fairly Hard
30-49	Hard
0-29	Very Hard

For help improving readability, try Hemingway App.

[krollins-mdb]

Thanks for cleaning up these tests, Dachary! LGTM.

[docs-builder-bot]

✨ Staging URL: https://preview-mongodbmongodb.gatsbyjs.io/realm/master/

🪵 Logs

• job log: 8fafa78e8cd17a9d39d0dbbda600ec2c5d5b063a