[FLINK-20344][dist] Change example value for default savepoint path flink-conf template.
[FLINK-20344][dist] Change example value for default savepoint path flink-conf template.

This makes it clearer that we recommend to have separate checkpoint and savepoint directories.

This closes #14215

greghogan/flink,greghogan/flink,greghogan/flink,greghogan/flink,greghogan/flink,greghogan/flink