refactoring test fixtures

runner/cmd_test.go

runner/config.go

runner/config_test.go

runner/fixtures/f1/base/odoo.yml

runner/fixtures/f1/base/postgres.yml

runner/fixtures/f1/base/ytt.yml

runner/fixtures/f1/base/ytt/patch1.yml

runner/fixtures/f1/beaver.yml

runner/fixtures/f1/environments/ns1/beaver.yml

runner/fixtures/f1/environments/ns1/odoo.yml

runner/fixtures/f1/environments/ns1/postgres.yaml

runner/fixtures/f1/environments/ns1/ytt.yaml

runner/fixtures/f1/environments/ns1/ytt/patch1.yml

runner/fixtures/f1/output.yaml

runner/fixtures/f1/vendir.yml

runner/fixtures/f2/base/odoo.yml

runner/fixtures/f2/base/postgres.yml

runner/fixtures/f2/base/ytt.yml

runner/fixtures/f2/base/ytt/patch1.yml

runner/fixtures/f2/beaver.yml