clean up mkdtemp usage

Committed via https://github.com/asottile/all-repos

doc/en/fixture.rst

@@ -2228,7 +2228,6 @@ file:
     # content of conftest.py
 
     import os
-    import shutil
     import tempfile
 
     import pytest
@@ -2236,12 +2235,11 @@ file:
 
     @pytest.fixture
     def cleandir():
-        old_cwd = os.getcwd()
-        newpath = tempfile.mkdtemp()
-        os.chdir(newpath)
-        yield
-        os.chdir(old_cwd)
-        shutil.rmtree(newpath)
+        with tempfile.TemporaryDirectory() as newpath:
+            old_cwd = os.getcwd()
+            os.chdir(newpath)
+            yield
+            os.chdir(old_cwd)
 
 and declare its use in a test module via a ``usefixtures`` marker:
 

testing/test_assertrewrite.py

@@ -1395,12 +1395,10 @@ class TestEarlyRewriteBailout:
             **{
                 "test_setup_nonexisting_cwd.py": """\
                     import os
-                    import shutil
                     import tempfile
 
-                    d = tempfile.mkdtemp()
-                    os.chdir(d)
-                    shutil.rmtree(d)
+                    with tempfile.TemporaryDirectory() as d:
+                        os.chdir(d)
                 """,
                 "test_test.py": """\
                     def test():