Add Support for Environment Variables as variable names in Line plotting yaml files

[CPKalb]

Describe the Enhancement

Currently, environment variables cannot be used as the variable name under fcst_var_val_1. Per Minna, using environment variables here doesn't work because the code that reads in the fcst_var_val is putting extra " " around the name of the fcst var val (set as env). This issue would be to enhance METplotpy to allow environment variables under fcst_var_val_1

Time Estimate

2 days?

Sub-Issues

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Relevant Deadlines

Needs to be completed and used in a use case by Sept 30

Funding Source

7707071

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Define Related Issue(s)

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• METplus, MET, METdataio, METviewer, METexpress, METcalcpy, METplotpy

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