build(deps): update platformdirs requirement from <4,>=3.1.1 to >=3.1.1,<5 (#10603)

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

tests/unit/test_dirs.py

@@ -1,4 +1,8 @@
-from dvc.dirs import global_config_dir
+import sys
+
+import pytest
+
+from dvc.dirs import global_config_dir, site_cache_dir
 from dvc.env import DVC_GLOBAL_CONFIG_DIR
 
 
@@ -6,3 +10,8 @@ def test_global_config_dir_respects_env_var(monkeypatch):
     path = "/some/random/path"
     monkeypatch.setenv(DVC_GLOBAL_CONFIG_DIR, path)
     assert global_config_dir() == path
+
+
+@pytest.mark.skipif(sys.platform != "linux", reason="Only for Unix platforms")
+def test_site_cache_dir_on_unix():
+    assert site_cache_dir() == "/var/tmp/dvc"