[BUG] Remove Language Argument If using not Robot 6 or greater

[d-biehl]

Describe the bug
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To Reproduce
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1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

If possible add some example source code like:

***Settings***
Library  Collections

***Test Cases***
a simple test
    do something    # this should shown something

Expected behavior
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Screenshots/ Videos
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Logs
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Desktop (please complete the following information):

• VS Code Version [e.g. 1.60]
• RobotCode Version [e.g. 0.3.2]
• OS: [e.g. Windows, Linux]
• Python Version [e.g. 3.9.7]
• RobotFramework Version [e.g. 4.0.0]
• Additional tools like robocop, robotidy

Additional context
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