Remove binary from repo and update .gitignore

Co-authored-by: dlevy-msft-sql <[email protected]>

Author: Copilot

.gitignore

@@ -36,6 +36,7 @@ linux-s390x/sqlcmd
 # Build artifacts in root
 /sqlcmd
 /sqlcmd_binary
+/modern
 
 # certificates used for local testing
 *.der