expose the resizable option for table column (#14757)

src/sql/azdata.proposed.d.ts

@@ -1021,6 +1021,11 @@ declare module 'azdata' {
 		 * The text to display on the column heading. 'value' property will be used, if not specified
 		 */
 		name?: string;
+
+		/**
+		 * whether the column is resizable. Default value is true.
+		 */
+		resizable?: boolean;
 	}
 
 	export interface IconColumnOptions {