fix: Change env var disabling OpenSearch security plugin (testcontainers#773)

This closes testcontainers#772

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Co-authored-by: David Ankin <daveankin@gmail.com>

Author: oelhammouchi

modules/opensearch/testcontainers/opensearch/__init__.py

@@ -57,7 +57,7 @@ def __init__(
 
         self.with_exposed_ports(self.port)
         self.with_env("discovery.type", "single-node")
-        self.with_env("plugins.security.disabled", "false" if security_enabled else "true")
+        self.with_env("DISABLE_SECURITY_PLUGIN", "false" if security_enabled else "true")
         if self._supports_initial_admin_password(str(image)):
             self.with_env("OPENSEARCH_INITIAL_ADMIN_PASSWORD", self.initial_admin_password)
         if security_enabled: