Implement fixtures for deploying FrostFS components

Exported from a private playground repo @ commit
ba8c88d7e11e8e8c17e54ca1317bc2dbf8b52204

Signed-off-by: Vitaliy Potyarkin <v.potyarkin@yadro.com>

tests/test_component_fixture_demo.py

@@ -0,0 +1,24 @@
+"""
+Demonstration of overrides for *_deployment fixtures
+"""
+import pytest
+
+from frostfs_testlib.component_tests.fixtures import alphabet_customize
+
+
+@pytest.fixture(scope="session")
+def deployment(alphabet_deployment):
+    print(f"{alphabet_deployment.prefix=}")
+    return alphabet_deployment
+
+
+def test_deployment(deployment):
+    assert deployment.node_count == 4
+    assert deployment.foo == "bar"
+
+
+@alphabet_customize(node_count=5)
+def test_deployment_custom(deployment):
+    assert deployment.node_count == 5
+    assert deployment.foo == "bar"
+    print(deployment.dir)