test(e2e): accept revisioned placeholder in coexistence test

Signed-off-by: Tinson Lai <tinsonl@nvidia.com>

Author: laitingsheng

e2e/python/test_sandbox_providers.py

@@ -345,7 +345,7 @@ def read_both_envs() -> str:
             assert result.exit_code == 0, result.stderr
             signing, api = result.stdout.strip().split("|", 1)
             assert signing == real_signing_secret
-            assert api == "openshell:resolve:env:SLACK_API_KEY"
+            assert _is_placeholder_for_env_key(api, "SLACK_API_KEY")
 
 
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