add root pe to diag_manifest.yaml file name

[rem1776]

Description
Adds the pe number to the output yaml so the atmos and ocean root pe's dont end up overwriting the file.

How Has This Been Tested?
the output yaml unit test on the amd box.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules
• New check tests, if applicable, are included
• make distcheck passes