Fix- Flutter & Dart SDK score

[lohanidamodar]

What does this PR do?

• Update flutter dependencies
• Update dart dependencies
• Update fixes for dart/flutter latest static analysis changes
• Update flutter docker image used for testing, as the image we were previously using has not been updated for 10months now.

Test Plan

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Related PRs and Issues

• https://github.com/appwrite/appwrite/issues/7211

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