Fix issue 1287 bug in subcritical powerplant report method (#1720)

* tag component individually

the change tags components that exist in the stream, e.g. for flue-gas streams, it tags N2, O2, NO, etc.; for water/steam streams, it only tags H2O, as the IAPWS95 property package only contains water.

* black .

* remove duplicated units in tags

removed duplicate pressure tag; removed dividend by 1000 for hmass and pressure as their unit are in J/kg and Pa, respectively

* black

* added test for tags, tag formats

modified the subcritical_power_plant.py with healer function for tags, tag formats, and tag_group to support a cleaner and simpler tags, tag formats, and tag_group test in the test file.

* black.

* underscore unused returns

* black .

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Co-authored-by: Keith Beattie <ksbeattie@lbl.gov>

Author: Lingyan90