Move %postInstall to %posttrans
    
    If policy update removes a module, %postInstall and therefore policy
    rebuild - `semodule -B -n ...` was run when old module is still
    installed, see
    https://docs.fedoraproject.org/en-US/packaging-guidelines/Scriptlets/#ordering
    It resulted to state when the old module is still built in the policy
    after update until another `semodule -B` is triggered.
    
    Moving %postInstall to %posttrans should solve this problem
    
    [skip changelog]