Fix master compatibility

[DominikKamp]

This fixes compilation for SCIP master on Mac with Homebrew.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 53.46%. Comparing base (1db095e) to head (94a6fb9).
Report is 83 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #988      +/-   ##
==========================================
+ Coverage   52.54%   53.46%   +0.92%     
==========================================
  Files          20       22       +2     
  Lines        4345     4962     +617     
==========================================
+ Hits         2283     2653     +370     
- Misses       2062     2309     +247     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[Joao-Dionisio]

It looks like it makes sense, @DominikKamp. But how would one test this? It's something that will impact everyone, that's why I'm a bit concerned about sending it untested.

[DominikKamp]

It affects Linux and Mac systems where there could be a brewed GMP. So better check this location as well. I have tested the updated branch and the tests seem to pass, otherwise you can just blame it on me.