Add pretty printing for exprts in Catch assertions

[hannes-steffenhagen-diffblue]

Without a pretty printer exprt's just show up as ? in
catch assertions, which isn't very helpful.

Other things that could be similarly printed are typets and (especially) irep_idts. These pretty printers are added from the use_catch header because I can’t think of a good reason why we’d need to avoid that, and this avoids annoying ? output when you forget to include an optional header (and UB because we have incompatible template instantiations in headers that don’t include the pretty printer, although that’s unlikely to cause actual problems).

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• Methods or procedures I have added are documented, following the guidelines provided in CODING_STANDARD.md.
• The feature or user visible behaviour I have added or modified has been documented in the User Guide in doc/cprover-manual/
• Regression or unit tests are included, or existing tests cover the modified code (in this case I have detailed which ones those are in the commit message).
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[codecov]

Codecov Report

Merging #5358 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop    #5358   +/-   ##
========================================
  Coverage    68.17%   68.17%           
========================================
  Files         1170     1170           
  Lines        96540    96540           
========================================
  Hits         65819    65819           
  Misses       30721    30721           

Flag	Coverage Δ
#cproversmt2	42.47% <ø> (ø)
#regression	65.38% <ø> (ø)
#unit	31.81% <ø> (ø)

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