Allow lists of input parameters as initial conditions

[pipliggins]

Description

Input parameters should not be able to be used as initial conditions (see #1261), but a bug was present where if more than one input parameter was provided but not all were used as initial conditions, the error warning could be bypassed.

Fixes #5154

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.80%. Comparing base (847723e) to head (2d5ea7e).
⚠️ Report is 2 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #5191   +/-   ##
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  Coverage    98.80%   98.80%           
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  Files          320      320           
  Lines        27034    27034           
========================================
  Hits         26711    26711           
  Misses         323      323           

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[rtimms]

Does this still allow for the case where there is an InputParameter in the initial conditions but there is only one solver? I.e. there is just a dict of inputs not a list of dicts. That case should still work IMO.

[pipliggins]

Does this still allow for the case where there is an InputParameter in the initial conditions but there is only one solver? I.e. there is just a dict of inputs not a list of dicts. That case should still work IMO.

Still works; going to edit this PR actually to make it a new feature that a list of input parameters can be provided and the inputs will be distributed correctly (useful for PyBoP).