Fix ENVars carrying between operations: make a copy of state ENV before updating.
@@ -175,7 +175,7 @@ def operation(func=None, pipeline_facts=None):
hosts = ensure_hosts_list(hosts)
# Config env followed by command-level env
- env = state.config.ENV
+ env = state.config.ENV.copy()
env.update(kwargs.pop('env', {}))
# Get/generate a hash for this op
