libgit2: some work on upgrading to version 0.23 (#677) [ci skip].
libgit2: some work on upgrading to version 0.23 (#677) [ci skip].

mirams/opencor,mirams/opencor,Fairly/opencor,Fairly/opencor,Fairly/opencor,mirams/opencor,Fairly/opencor,Fairly/opencor,mirams/opencor,mirams/opencor