:bug: Removed false positive duplicate global handler issue

[sadlowskij]

Proposed Changes

This commit stops the same handler to be added to globalHandlerMap twice. This lead to an error, where it reported a duplicate handler even though it was the same handler twice. This can happen with intentMaps, e. g. you have an intentMap like this:

  routing: {
    intentMap: {
      'AMAZON.HelpIntent': 'HelpIntent',
    }
  },

and a handler like this:

  @Handle({global: true, intents: ['HelpIntent', 'AMAZON.HelpIntent']})
  help(): Promise<void> {
    throw new Error('just a test');
  }

I am aware that in most cases, you should just not use AMAZON.HelpIntent in the intents array and it works just fine. However, if you are using one and the same component in multiple projects that might have different intentmaps, this might actually make things easier. Also, even though this might not be the best implementation, I don't think it was intended to treat the same handler as duplicate in this specific scenario in the first place.

Types of Changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• [x] My code follows the code style of this project
• [ ] My change requires a change to the documentation
• [ ] I have updated the documentation accordingly
• [ ] I have added tests to cover my changes
• [ ] All new and existing tests passed