Fix Sonar issue, formatting (#99)

* Fix Sonar issue, formatting

* Remove dev dependencies from requirements.tzt

* Fix unit test failure

tests/test_print_table.py

@@ -7,13 +7,13 @@ from app.print_table import generate_prefix_string  # pragma: no cover
 
 def test_generate_prefix_string_small() -> None:
     """TEST: Verifies if a small prefix list results in one line."""
-    test_query = ["abc", "def"]
-    result = generate_prefix_string(prefixes=test_query)
+    test_query: list[str] = ["abc", "def"]
+    result: str | None = generate_prefix_string(prefixes=test_query)
     assert result == "abc, def\n"
 
 
 def test_generate_prefix_string_large() -> None:
     """TEST: Verifies if a large prefix list results in multiple lines."""
-    test_query = ["abc", "def", "ghi", "jkl", "mno", "pqr"]
-    result = generate_prefix_string(prefixes=test_query)
+    test_query: list[str] = ["abc", "def", "ghi", "jkl", "mno", "pqr"]
+    result: str | None = generate_prefix_string(prefixes=test_query)
     assert result == "abc, def, ghi, jkl\nmno, pqr\n"