Remove util_make_unique

[tautschnig]

With the move to C++ 17 we can use std::make_unique instead.

• 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

Attention: 20 lines in your changes are missing coverage. Please review.

Comparison is base (7979553) 79.09% compared to head (c17285c) 79.10%.
Report is 1 commits behind head on develop.

❗ Current head c17285c differs from pull request most recent head 096f454. Consider uploading reports for the commit 096f454 to get more accurate results

Files	Patch %	Lines
src/goto-instrument/cover.cpp	80.00%	3 Missing ⚠️
jbmc/src/jbmc/jbmc_parse_options.cpp	66.66%	2 Missing ⚠️
src/analyses/invariant_propagation.cpp	0.00%	2 Missing ⚠️
jbmc/src/java_bytecode/java_bytecode_language.h	0.00%	1 Missing ⚠️
src/analyses/goto_rw.cpp	50.00%	1 Missing ⚠️
...lyses/variable-sensitivity/abstract_value_object.h	0.00%	1 Missing ⚠️
src/ansi-c/ansi_c_language.h	0.00%	1 Missing ⚠️
src/cbmc/cbmc_parse_options.cpp	83.33%	1 Missing ⚠️
src/cpp/cpp_language.h	0.00%	1 Missing ⚠️
src/goto-analyzer/build_analyzer.cpp	93.75%	1 Missing ⚠️
... and 6 more

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #8032      +/-   ##
===========================================
+ Coverage    79.09%   79.10%   +0.01%     
===========================================
  Files         1699     1698       -1     
  Lines       196512   196502      -10     
===========================================
+ Hits        155428   155440      +12     
+ Misses       41084    41062      -22     

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[thomasspriggs]

@martin-cs This seems to need your review due to a change in /src/json-symtab-language/

[thomasspriggs]

@martin-cs This seems to need your review due to a change in /src/json-symtab-language/

That should be resolved by the addition of extra code owners in #8087

I think we still need review from one of @qinheping @feliperodri or @remi-delmas-3000 due to the update in src/goto-synthesizer/

[feliperodri]

Changes in goto/synthesizer LGTM.