component/git: fix library path

without the fix, we get this on Debian 12 compilation:

[2023-06-13 16:19:14,522] INFO     Cloning into '/opt/slapgrid/575c4158f610d2eb6886264b60654ce8/parts/shellinabox-git-repository'...
[2023-06-13 16:19:14,526] INFO     /opt/slapgrid/shared/git/e7d6bd941dfb709752c59e8f2a2b9127/libexec/git-core/git-remote-https: error while loading shared libraries: libcurl.so.4: cannot open shared object file: No such file or directory
[2023-06-13 16:19:14,551] INFO     While:
[2023-06-13 16:19:14,551] INFO       Installing shellinabox-git-repository.