goto_analyzer_parse_optionst is not a messaget

[romainbrenguier]

This class already inherits a log field referencing the same thing.

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

[allredj]

✔️
Passed Diffblue compatibility checks (cbmc commit: 27baa38).
Build URL: https://travis-ci.com/diffblue/test-gen/builds/107978432