Revert "Add json-c"
    
    Adding json-c to flatpak-common broke dnf when installing
    module-build-macros srpm build root:
    
    DEBUG util.py:444:  Traceback (most recent call last):
    DEBUG util.py:444:    File "/usr/bin/dnf", line 57, in <module>
    DEBUG util.py:444:      from dnf.cli import main
    DEBUG util.py:444:    File "/usr/lib/python3.10/site-packages/dnf/__init__.py", line 30, in <module>
    DEBUG util.py:444:      import dnf.base
    DEBUG util.py:444:    File "/usr/lib/python3.10/site-packages/dnf/base.py", line 29, in <module>
    DEBUG util.py:444:      import libdnf.transaction
    DEBUG util.py:444:    File "/usr/lib/python3.10/site-packages/libdnf/__init__.py", line 12, in <module>
    DEBUG util.py:444:      from . import conf
    DEBUG util.py:444:    File "/usr/lib/python3.10/site-packages/libdnf/conf.py", line 13, in <module>
    DEBUG util.py:444:      from . import _conf
    DEBUG util.py:444:  ImportError: libjson-c.so.5: cannot open shared object file: No such file or directory
    
    This reverts commit cd2866d1fc58e10bf23dc36336a570c7a9daad18.