Error advanced-osgi formating (#11382)

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documentation/advanced/advanced-osgi.asciidoc

 The easiest way to convert regular maven-based Vaadin application into a valid OSGi bundle consists of five steps:
 
 * Change packaging type to `jar` in your `pom.xml`:
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 [source, xml]
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     <packaging>jar</packaging>
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 * Change the scope for all vaadin dependencies from default to `provided`, like this:
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 [source, xml]
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         <dependency>
         </dependency>
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 * Add OSGi-related dependencies to the project
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 [source, xml]
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         <groupId>com.vaadin</groupId>
         </dependency>
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 * Setup necessary plugins for building the project:
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 [source, xml]
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  <build>
     </build>
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 * Add bundle script (`bnd.bnd`) into the project root folder:
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 [source, text]
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 Bundle-Name: ${project.name}