Bump CBMC version

[zhassan-aws]

Description of changes:

Upgrade CBMC version to latest (5.93.0).

Resolved issues:

Resolves #2650

Related RFC:

Optional #ISSUE-NUMBER.

Call-outs:

Testing:

• How is this change tested? Added a test

• Is this a refactor change? No

Checklist

• Each commit message has a non-empty body, explaining why the change was made
• Methods or procedures are documented
• Regression or unit tests are included, or existing tests cover the modified code
• My PR is restricted to a single feature or bugfix

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 and MIT licenses.

[zhassan-aws]

I ran the relevant test that failed in the performance benchmarks (check_insert_two_concrete) multiple times locally with the two versions of CBMC, and the time was about the same with both versions, so the results are in the noise.