Pinned ffi-compiler2 version to 2.0.1

[maxirmx]

Metanorma PR checklist

• Breaking changes (list related PRs)
• Documentation update required (create task for this)
• External dependency introduced (documentation update need)
• Gem with native library introduced

Workaround for https://github.com/metanorma/ruby-libmspack/issues

[maxirmx]

Some tests are failing because of #222

[maxirmx]

I will go patch excavate as libmspack is used by it.
Otherwise all 'intermediate' build we keep failing (fontist, etc ...)

[ronaldtse]

Is there any code to upstream here?

[maxirmx]

Is there any code to upstream here?

There is a change in ffi_compiler2 and this change is not portable.
My best thought is to use mini_portile instead of ffi_compiler2 but I believe it needs to be pre-approved.

[ronaldtse]

Sorry @maxirmx I don’t understand what “pre-approved” means here.

[maxirmx]

Sorry @maxirmx I don’t understand what “pre-approved” means here.

I mean that ruby-libmspack maintainer should be ready to accept PR that changes build system and it would good to discuss it in advance

[maxirmx]

This PR shall cover all gems that use excavate
fontist/excavate#26

[maxirmx]

Closing this PR since excavate path closes the issue
It is a temporary solution anyway. Long term we need a fix in ruby-libmspack.