Fix Boolean option without value does not properly work with argument #1309

[czpilar]

Resolves #1309

[fmbenhassine]

Thank you for opening the issue and contributing a fix!

The change set LGTM 👍 I just find the introduction of the conversion service a bit disruptive/intrusive (see its impact on breaking some public APIs) for what it is used for at the moment (just converting a boolean value). Since I am targeting this fix for a patch release, I will update that conversion logic to a simpler version for now, and we can introduce the conversion service in a later minor iteration if needed.

[fmbenhassine]

Rebased and merged as 0ece35e.

As mentioned previously, I kept only the fix in the parser without the introduction of a conversion service. I adapted the isBooleanValue function to a simpler version accordingly.

Thank you for your contribution!

[czpilar]

@fmbenhassine Sure, simplifying is not a problem. I used the ConversionService because it is used in other parts of the project, and I thought it was the preferred way to convert values.