fix: don't throw TypeError: Invalid Version: null in sidekick when emulator is stopped immediately after start

[Fatme]

TypeError: Invalid Version: null error is shown is Sidekick when emulator is stopped immediately after start. This happens because emulator is stopped too early and it is not fully initialized. In this case reported emulator is with version: null and the semver comparison fails. So we need to ensure the device's version is not null before comparison.

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• Tests for the changes are included.

What is the current behavior?

TypeError: Invalid Version: null error is thrown in Sidekick when emulator is stopped immediately after start.

What is the new behavior?

No error is thrown in Sidekick when emulator is stopped immediately after start.

[rosen-vladimirov]

After deciding what will happen if deviceInfo is null.