ES::read should only try to read in preserved system vectors

[vikramvgarg]

Currently, ES::read tries to find all the vectors the system holds while reading a solution file.

Some vectors like sensitivity_rhs and adjoint_based_lift vectors are used temporarily for post-processing, and ordinarily should not be part of the I/O unless.

We should only read in preserved vectors, and throw an error if ES::read cannot find a preserved vector while reading a file. @roystgnr