Additional explanations to the example files and fixing result.ref file in examples/bsse/water

[BariumOxide13716]

Reminder

• Have you linked an issue with this pull request?
• Have you added adequate unit tests and/or case tests for your pull request?
• Have you noticed possible changes of behavior below or in the linked issue?
• Have you explained the changes of codes in core modules of ESolver, HSolver, ElecState, Hamilt, Operator or Psi? (ignore if not applicable)

Linked Issue

Fix #5472

Unit Tests and/or Case Tests for my changes

Unit tests not required

What's changed?

My changes updates the examples/bsse/water/result.ref file such that run.sh reports "job succeeded" after it is executed.
Some comments are added to the example INPUT and KPT files to more clearly explain what is happening in these files.

Any changes of core modules? (ignore if not applicable)

• Example: I have added a new virtual function in the esolver base class in order to ...

[BariumOxide13716]

hi @maki49 and @pxlxingliang , could you please help review the changes made in these files and let me know if any changes need to be made?