fix the mistake of swapping function parameters of read_proc_environ_var
    
    Resolves: bz2024976
    Upstream: Fedora
    Conflict: None
    
    commit 5111c01334046dd4176d4446075b02106fb9db4a
    Author: Coiby Xu <coxu@redhat.com>
    Date:   Mon Feb 7 08:08:01 2022 +0800
    
        fix the mistake of swapping function parameters of read_proc_environ_var
    
        _is_osbuild fails because it expects the 1st and 2nd function parameter
        to be the environment variable and environ file path respectively. Fix
        it by swapping the parameters in read_proc_environ_var.
    
        Note the osbuild environ file path is defined in _OSBUILD_ENVIRON_PATH
        so _is_osbuild can be unit-tested by overwriting _OSBUILD_ENVIRON_PATH.
    
        Fixes: 6a3ce83 ("fix the error of parsing the container environ variable for osbuild")
        Signed-off-by: Coiby Xu <coxu@redhat.com>
        Reviewed-by: Pingfan Liu <piliu@redhat.com>