[CL] Optional functionality for equilibrium reactant behavior

This MR adds an optional keyword <reaction_irreversibility> to enable additional functionality for the Phreeqc chemical solver. Validation is done by adding a test calciteDissolvePrecipitateOnly.prj based on the calcite test:

https://www.opengeosys.org/docs/benchmarks/reactive-transport/calcite/

Since results are for validation only, I think it is not necessary to add anything to the web description of the calcite test.

1. Feature description was added to the changelog
2. Tests covering your feature were added?
3. Any new feature or behavior change was documented?