test: very_good_flutter_plugin doesn't have full code coverage

[alestiago]

Description

The coverage of the template is not 100%, it's 86%.

Reproductive steps

1. Get the Very Good Flutter Plugin brick (from .):

mason get

1. Generate Very Good Flutter Plugin (from .):

mason make very_good_flutter_plugin -o output/

3. Run tests (from output/):

very_good test -j 4 --recursive --optimization --coverage --test-randomize-ordering-seed random --min-coverage 100

Expected behaviour

Coverage should be 100%

Requirements

• [ ] Coverage should be 100%
• [ ] Update workflow to check coverage is 100%

[tomarra]

Assigning to @wolfenrain given that it has to do with Fluttium.

[alestiago]

Closed by #89

[alestiago]

Re-opening until we check again for 100% coverage on CI:

https://github.com/VeryGoodOpenSource/very_good_templates/blob/f7e6c45929b1c9121338cd0f28ff5687c5527c2d/.github/workflows/very_good_flutter_plugin.yaml#L86