Removing reference to deleted application plugin #1739

The issue is not linked to this change but "application plugin" appeared
in the log so I searched for it but could only find it in the SDK
product which is not at all used by the issue issuer.
But I fixed it.

Author: jan

io.sloeber.product.sdk/sdk.product

@@ -51,8 +51,6 @@ https://github.com/sloeber/arduino-eclipse-plugin/graphs/contributors
       </win>
    </launcher>
 
-   <intro introId="io.sloeber.application.intro"/>
-
    <vm>
    </vm>