test: code exec on mac (#1549)

Summary:
1. adds option to not use bwrap for code execution
2. disable bwrap when running tests on macs

Test Plan:
```
LLAMA_STACK_CONFIG=fireworks pytest -s -v tests/integration/agents/test_agents.py --safety-shield meta-llama/Llama-Guard-3-8B --text-model meta-llama/Llama-3.1-8B-Instruct
```

Verify code_interpreter result in logs

INFO 2025-03-11 08:10:39,858
llama_stack.providers.inline.agents.meta_reference.agent_instance:1032
agents: tool
call code_interpreter completed with result:
content='completed\n\n541\n' error_message=None error_code=None
         metadata=None

tests/integration/conftest.py

@@ -6,12 +6,17 @@
 import inspect
 import itertools
 import os
+import platform
 import textwrap
 
 from dotenv import load_dotenv
 
+from llama_stack.log import get_logger
+
 from .report import Report
 
+logger = get_logger(__name__, category="tests")
+
 
 def pytest_configure(config):
     config.option.tbstyle = "short"
@@ -24,6 +29,10 @@ def pytest_configure(config):
         key, value = env_var.split("=", 1)
         os.environ[key] = value
 
+    if platform.system() == "Darwin":  # Darwin is the system name for macOS
+        os.environ["DISABLE_CODE_SANDBOX"] = "1"
+        logger.info("Setting DISABLE_CODE_SANDBOX=1 for macOS")
+
     if config.getoption("--report"):
         config.pluginmanager.register(Report(config))