Stale flows in table 46, 47 and 44 when SNAT is disabled (Conntrack Based)

Stale flows in table 46, 47 and 44 when SNAT is disabled

Steps to reproduce
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1) Create internal n/w external n/w.
2)Create a router and add the internal n/w
3)Set the external n/w as the router g/w
4)Clear router g/w set.

Expected Output
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table 46, 47 and 44 should be cleared.

Actual Output
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Stale flows observed in table 46, 47 and 44