Expose the energy dissipation state variable in BushingForce

[nickbianco]

Fixes issue #4042

Brief summary of changes

This change exposes the "dissipated energy" state variable allocated by the SimTK::Force::LinearBushing that is internal to BushingForce. This fixes the bug in #4042, which occurred because the size of the auxiliary state vector reserved by Moco did not match SimTK::State::getZ(). This happened because Moco reserves state vectors based on the number of state variables reported by each Component, but BushingForce did not report the "dissipated energy" state as part of the system, even though a slot for it is reserved in the SimTK::State.

For convenience, I added the Output "statebounds_dissipated_energy", which Moco will use to automatically set the bounds on the energy dissipation state variable (i.e., so users do not have to call setStateInfo).

Testing I've completed

Added tests to testMocoInterface.cpp and testForces.cpp.

Looking for feedback on...

CHANGELOG.md (choose one)

• updated.

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This change is 

[nickbianco]

FYI @nicos1993 and @stingjp.

[aymanhab]

Reviewed 3 of 4 files at r1, 2 of 2 files at r2, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @nickbianco)

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CHANGELOG.md line 93 at r2 (raw file):

- Fixed bugs in `PolynomialPathFitter` when too few coordinate samples were provided. (#4039)
- Exposed the "dissipated energy" state variable allocated by the `SimTK::Force::LinearBushing` that is internal to `BushingForce`. 
  This changed fixed a bug in Moco, where adding a `BushingForce` led to a segfault due to a mismatch between the size of the 

typo (changed -> change?)

[aymanhab]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @nickbianco)

[nickbianco]

Thanks @aymanhab!