Update mssql.json (#1623)

Misleading description for dropping a column.

Author: trevorcarter83

snippets/mssql.json

@@ -115,7 +115,7 @@
 			"\tDROP COLUMN ${1:ColumnName}",
 			"GO"
 		],
-		"description": "Add a new column to a Table"
+		"description": "Drop a column from a Table"
 	},
 
 	"Select rows from a Table or a View": {