Add close() method to RestCatalog (apache#2403)

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Part of apache#2399 

# Rationale for this change

This PR introducs the implementation of `close()` method to the
`RestCatalog`.

And add corresponding test case which following the test pattern in
apache#2390

## Are these changes tested?

Yes

## Are there any user-facing changes?

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Author: dingo4dev

pyiceberg/catalog/rest/__init__.py

@@ -876,3 +876,10 @@ def drop_view(self, identifier: Union[str]) -> None:
             response.raise_for_status()
         except HTTPError as exc:
             _handle_non_200_response(exc, {404: NoSuchViewError})
+
+    def close(self) -> None:
+        """Close the catalog and release Session connection adapters.
+
+        This method closes mounted HttpAdapters' pooled connections and any active Proxy pooled connections.
+        """
+        self._session.close()

tests/catalog/test_rest.py

@@ -1845,3 +1845,76 @@ def test_rest_catalog_with_google_credentials_path(
     assert len(history) == 1
     actual_headers = history[0].headers
     assert actual_headers["Authorization"] == expected_auth_header
+
+
+class TestRestCatalogClose:
+    """Tests RestCatalog close functionality"""
+
+    EXPECTED_ADAPTERS = 2
+    EXPECTED_ADAPTERS_SIGV4 = 3
+
+    def test_catalog_close(self, rest_mock: Mocker) -> None:
+        rest_mock.get(
+            f"{TEST_URI}v1/config",
+            json={"defaults": {}, "overrides": {}},
+            status_code=200,
+        )
+
+        catalog = RestCatalog("rest", uri=TEST_URI, token=TEST_TOKEN)
+        catalog.close()
+        # Verify session still exists after close the session pooled connections
+        assert hasattr(catalog, "_session")
+        assert len(catalog._session.adapters) == self.EXPECTED_ADAPTERS
+        # Second close should not raise any exception
+        catalog.close()
+
+    def test_rest_catalog_close_sigv4(self, rest_mock: Mocker) -> None:
+        catalog = None
+        rest_mock.get(
+            f"{TEST_URI}v1/config",
+            json={"defaults": {}, "overrides": {}},
+            status_code=200,
+        )
+
+        catalog = RestCatalog("rest", **{"uri": TEST_URI, "token": TEST_TOKEN, "rest.sigv4-enabled": "true"})
+        catalog.close()
+        assert hasattr(catalog, "_session")
+        assert len(catalog._session.adapters) == self.EXPECTED_ADAPTERS_SIGV4
+
+    def test_rest_catalog_context_manager_with_exception(self, rest_mock: Mocker) -> None:
+        """Test RestCatalog context manager properly closes with exceptions."""
+        catalog = None
+        rest_mock.get(
+            f"{TEST_URI}v1/config",
+            json={"defaults": {}, "overrides": {}},
+            status_code=200,
+        )
+
+        try:
+            with RestCatalog("rest", uri=TEST_URI, token=TEST_TOKEN) as cat:
+                catalog = cat
+                raise ValueError("Test exception")
+        except ValueError:
+            pass
+
+        assert catalog is not None and hasattr(catalog, "_session")
+        assert len(catalog._session.adapters) == self.EXPECTED_ADAPTERS
+
+    def test_rest_catalog_context_manager_with_exception_sigv4(self, rest_mock: Mocker) -> None:
+        """Test RestCatalog context manager properly closes with exceptions."""
+        catalog = None
+        rest_mock.get(
+            f"{TEST_URI}v1/config",
+            json={"defaults": {}, "overrides": {}},
+            status_code=200,
+        )
+
+        try:
+            with RestCatalog("rest", **{"uri": TEST_URI, "token": TEST_TOKEN, "rest.sigv4-enabled": "true"}) as cat:
+                catalog = cat
+                raise ValueError("Test exception")
+        except ValueError:
+            pass
+
+        assert catalog is not None and hasattr(catalog, "_session")
+        assert len(catalog._session.adapters) == self.EXPECTED_ADAPTERS_SIGV4