Replace `<stuff>' with '<stuff>'

[owen-mc-diffblue]

This changes the error message from
failed to load class `java.nio.file.Path'
to
failed to load class 'java.nio.file.Path'

• Each commit message has a non-empty body, explaining why the change was made.
• 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).
• My commit message includes data points confirming performance improvements (if claimed).
• My PR is restricted to a single feature or bugfix.
• White-space or formatting changes outside the feature-related changed lines are in commits of their own.

[danpoe]

That's probably intentional as the pattern with left hand ` and right hand ' occurs more frequently in the code than two single quotes.

[owen-mc-diffblue]

Thanks for pointing that out @danpoe , on closer inspection I see that you are right. In that case, I'm expanding the scope of this PR to replace ` with ' everywhere where the closing delimiter is '. I think this is a much more common usage of punctuation.

[tautschnig]

@owen-jones-diffblue Why is this a desirable change?

[kroening]

This is certainly a very unimportant point one could get very excited about.
https://www.cl.cam.ac.uk/~mgk25/ucs/quotes.html
We could add quotebegin and quoteend stream modifiers. The result could then be quotes, a change in font, etc., depending on target.

[owen-mc-diffblue]

@tautschnig As the link that @kroening posted says, the convention of quoting `text like this' looks odd in most modern fonts.

I appreciate this is not a majorly important change, but it's something that annoys me. I think it makes the output look unprofessional. It was a treat I gave myself after doing some very tedious work I didn't really want to do. The prompt was someone asking about an error message, and they obviously thought it was a mistake that there was a ` instead of a '.

[tautschnig]

@owen-jones-diffblue Thank you for elaborating - it would be really helpful to have the "Why?" answered in commit messages (always, not just here). That settled, we are probably very inconsistent about our quoting and thus this is a really good step forward! My only reservation is that there may be users parsing warnings and thus we'd (negatively) surprise them, but arguably no one should rely on formatting of plain-text messages so I'm ok to ignore this one.

[codecov-io]

Codecov Report

Merging #4875 into develop will decrease coverage by <.01%.
The diff coverage is 17.27%.

@@             Coverage Diff             @@
##           develop    #4875      +/-   ##
===========================================
- Coverage    69.09%   69.09%   -0.01%     
===========================================
  Files         1298     1298              
  Lines       106944   106951       +7     
===========================================
  Hits         73895    73895              
- Misses       33049    33056       +7

Impacted Files	Coverage Δ
src/goto-programs/goto_convert.cpp	91.18% <ø> (ø)	⬆️
src/langapi/mode.cpp	100% <ø> (ø)	⬆️
src/goto-symex/symex_function_call.cpp	87.23% <ø> (ø)	⬆️
src/analyses/goto_check.cpp	78.99% <ø> (ø)	⬆️
src/cbmc/cbmc_parse_options.cpp	76.47% <ø> (ø)	⬆️
src/cpp/cpp_typecheck_bases.cpp	62.68% <ø> (ø)	⬆️
jbmc/src/janalyzer/janalyzer_parse_options.cpp	45.7% <ø> (ø)	⬆️
src/goto-analyzer/show_on_source.cpp	95.45% <ø> (ø)	⬆️
src/solvers/smt2/smt2_conv.cpp	60.01% <ø> (ø)	⬆️
src/util/config.cpp	56.02% <ø> (ø)	⬆️
... and 79 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 7051df5...db75f0c. Read the comment docs.