HPCC-9833 Fix exception leaking in ESP ECLWatch service code

Add calls to e->Release() in multiple places where it should be called
to release exceptions.
Merge pull request #4869 from wangkx/h9833

HPCC-9833 Fix exception leaking in ESP ECLWatch service code

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>