Assert proper error when Value bar is less then Custom Label start value

[hasnentai]

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

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

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
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  valueBar: [
                  ValueBar(
                    value: 20,
                    offset: 300,
                  )
                ],
                enableGaugeAnimation: true,
                customLabels: [
                  CustomRulerLabel(text: "Hello One", value: value),
                  CustomRulerLabel(text: "Hello Two", value: 60),
                ],