Removes a leftover width test string

doc/user/project/clusters/serverless/index.md

@@ -450,7 +450,6 @@ To run a function locally:
 
 > Introduced in GitLab 11.5.
 
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 Serverless applications are an alternative to [serverless functions](#deploying-functions).
 They're useful in scenarios where an existing runtime does not meet the needs of
 an application, such as one written in a language that has no runtime available.