Clean up sql-server-docs-contribute.md

Removed redundant 'Thank you.' and added a test line.

Author: MashaMSFT

docs/sql-server/sql-server-docs-contribute.md

@@ -129,5 +129,3 @@ Explore the [sql-docs repository](https://github.com/MicrosoftDocs/sql-docs) on
 Find an article, submit a change, and help the SQL Server community.
 
 Thank you.
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-test