Check completeness of help output in CI

[tautschnig]

This commit adds a new script to run post-build that assesses the
completeness of --help for all binaries except for goto-cc.

• Each commit message has a non-empty body, explaining why the change was made.
• n/a Methods or procedures I have added are documented, following the guidelines provided in CODING_STANDARD.md.
• n/a 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).
• n/a My commit message includes data points confirming performance improvements (if claimed).
• My PR is restricted to a single feature or bugfix.
• n/a White-space or formatting changes outside the feature-related changed lines are in commits of their own.

[codecov]

Codecov Report

Merging #6917 (880725c) into develop (7ca319a) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop    #6917   +/-   ##
========================================
  Coverage    77.86%   77.86%           
========================================
  Files         1569     1569           
  Lines       180995   180995           
========================================
  Hits        140929   140929           
  Misses       40066    40066           

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.