change parameter filegid of file_groupownership template to gid_or_name
explain its behavior

…rship template from filegid to gid_or_name

change the parameter name from filgeid to gid_or_name
additionally, use the -group parameter instead of -gid parameter in find command invocation
the -group parameter accepts both gid and group names, where the -gid parameter accepts only gid

establish a new variable which carries information if the parameter is a gid or a group name

decide if to use group ID or group name based on the variable declared in the preprocessing function
change parameter name from file_gid to gid_or_name

…templates into shared module

The test did not account for a case when a filepath is a directory and it does not exist on the system.
Also the test made use of is_directory parameter which is only available at runtime when building the template and it is not saved anywhere.
Instead of this parameter, scenarios now check if the path ends with a slash. This signifies the filepath is a directory as mentioned in the tempate documentation.

…le_owner template

These test scenarios would not work correctly if the filepath parameter was a directory.

This rule uses directory + regex, it needs a special test scenario because the template does only generic testing.

…s exists before using it in test scenario

it migt not exist in FEdora container which is used as test environment

the missing_file_test test scenario should fail, not pass.
At the same time, we actually can't create a new failing test scenario - removing the ssh private key will break the testing workflow.