Add `payu` in benchcab conda environment

[abhaasgoyal]

Make current version of payu (1.1.2) compatible with building conda environment. Fixes #235

Merge Message

The following comment was used as a guideline for the changes: https://github.com/payu-org/payu/issues/413#issuecomment-1907945016

Further implications:

• Since conda uses strict channel priority, packages from conda-forge take priority over packages defined in accessnri/coecms
• coecms is used to build payu due to deploying yamanifest

[codecov[bot]]

Codecov Report

Attention: 5 lines in your changes are missing coverage. Please review.

Comparison is base (e3ab664) 59.13% compared to head (47f050b) 59.13%. Report is 20 commits behind head on main.

Files	Patch %	Lines
benchcab/benchcab.py	0.00%	4 Missing :warning:
tests/test_config.py	97.36%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #247 +/- ## ======================================= Coverage 59.13% 59.13% ======================================= Files 29 29 Lines 2129 2129 ======================================= Hits 1259 1259 Misses 870 870 ```

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