Fallback to current datetime when failing on parse session json file

[eliasyishak]

Fixes:

• [flutter_tools] FormatException: Unexpected end of input (at character 1) decoding analytics session data flutter/flutter#143792

This PR changes the error handling behavior when attempting to parse the json file for session data. Instead of trying to parse the newly created file, it will set the current session to the current datetime. This is possibly a race condition issue that will be investigated further in the below issue.

• Investigate race conditions on analytics related files #166

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[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:unified_analytics	5.8.3	ready to publish	unified_analytics-v5.8.3
package:cli_config	0.1.2	already published at pub.dev
package:extension_discovery	2.0.1-wip	WIP (no publish necessary)
package:graphs	2.3.2-wip	WIP (no publish necessary)

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[christopherfujino]

This LGTM. once this merges, I think you should create a 5.8.0+1 hotfix version to CP to Flutter 3.19