fix(test): Catch correct ConnectionError in test_deflate_on_oom

Turns out that `except ConnectionError` catches the `ConnectionError`
from the standard library, while what needs to be caught is the
(different) `ConnectionError` from the `requests` package.

Signed-off-by: Patrick Roy <roypat@amazon.co.uk>

tests/integration_tests/functional/test_balloon.py

@@ -7,6 +7,7 @@
 from subprocess import TimeoutExpired
 
 import pytest
+import requests
 from tenacity import retry, stop_after_attempt, wait_fixed
 
 from framework.utils import check_output, get_free_mem_ssh
@@ -209,7 +210,7 @@ def test_deflate_on_oom(uvm_plain_any, deflate_on_oom):
 
     try:
         balloon_size_after = test_microvm.api.balloon_stats.get().json()["actual_mib"]
-    except ConnectionError:
+    except requests.exceptions.ConnectionError:
         assert (
             not deflate_on_oom
         ), "Guest died even though it should have deflated balloon to alleviate memory pressure"