chore: finish #194: minor codestyle and lint cleanups

            # Iterate through node

            for variant in variants:

                # Acquire variant name

                name = variant['name']

                # Prepare variant environment

                if variant['environment']:

                    node_environ = dict(environ)

                    environ.update(variant['environment'])

                # Register job

                jobs[variant['name']] = self.job(node, variant['name'], data,

                                                 global_values)

                jobs[name] = self.job(node, name, data, global_values)

                # Prepare variant variables

                if variant['environment']:

                    jobs[variant['name']]['variables'].update(variant['environment'])

                    jobs[name]['variables'].update(variant['environment'])

                # Validate job script

                if not jobs[variant['name']]['options']['disabled'] and not jobs[

                        variant['name']]['script']:

                if not jobs[name]['options']['disabled'] and not jobs[name]['script']:

                    raise ValueError(

                        f"Missing \"script\" key for \"{jobs[variant['name']]['stage']} / {jobs[variant['name']]['name']}\""

                        f"Missing \"script\" key for \"{jobs[name]['stage']}" \

                            f" / {jobs[name]['name']}\""

                    )

                # Append unknown stage if required

                if jobs[variant['name']]['options']['disabled'] and jobs[variant['name']][

                        'stage'] == GitLab.JOB_STAGE_DEFAULT and GitLab.JOB_STAGE_DEFAULT not in stages:

                if jobs[name]['options']['disabled'] \

                        and jobs[name]['stage'] == GitLab.JOB_STAGE_DEFAULT \

                            and GitLab.JOB_STAGE_DEFAULT not in stages:

                    stages[GitLab.JOB_STAGE_DEFAULT] = list(stages.values())[-1] + 1

                # Validate job stage

                if jobs[variant['name']]['stage'] not in stages:

                if jobs[name]['stage'] not in stages:

                    raise ValueError(

                        f"Unknown stage \"{jobs[variant['name']]['stage']}\" for \"{jobs[variant['name']]['name']}\""

                        f"Unknown stage \"{jobs[name]['stage']}\"" \

                            f" for \"{jobs[name]['name']}\""

                    )

                # Restore variant environment