docs(v-banner): fixes VBanner's usage, which was not updated correctly (#15241)
docs(v-banner): fixes VBanner's usage, which was not updated correctly (#15241)

fixes #15236

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## Description
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This PR fixes #15236


## Types of changes
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- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
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- [ ] Improvement/refactoring (non-breaking change that doesn't add any
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