Adding notes on the practice of using `module reset`

[bdu-birhanu]

Overview

Notes on the practice of using module reset command at the start of sbatch scripts.

Proposed Changes

• Adding notes on the practice of `module reset' in modules and applications page.
• crosslink at: Job submission, Practical sbatch, GPU, and OOD pages.

Related Issues

Fixes #524

[bdu-birhanu]

Change py designation in code blocks back to bash where bash is being used

Just fixed.