Update libcyaml dependency in cstest to 1.4.2

[thestr4ng3r]

Your checklist for this pull request

• I've documented or updated the documentation of every API function and struct this PR changes.
• I've added tests that prove my fix is effective or that my feature works (if possible)

Detailed description

1.4.2 contains a fix to replace static_assert calls by a more portable variant. This is relevant for building on e.g. Mac OS X 10.5.

Test plan

Build with MacPorts gcc 7.5.0 on Mac OS X 10.5 and -DCAPSTONE_BUILD_CSTEST=1. (Hint: there are other issues in the cstest code, but those can be addressed separately)

[Rot127]

Hint: there are other issues in the cstest code, but those can be addressed separately

Which one? Can you open an issue about please.

[thestr4ng3r]

Hint: there are other issues in the cstest code, but those can be addressed separately

Which one? Can you open an issue about please.

strndup usage, opened an issue: #2517

[XVilka]

@kabeor and this one

[Rot127]

strndup usage, opened an issue: #2517

Alright. Thanks for the issue! I didn't make it portable (also not for Windows) because it took too much time already. And with cstest_py we can technically still test everything on all platforms. Another one is the dir walking. Also doesn't work Windows I think.