Revert "Optimize euicc invocations by keeping channel open sessi..."

Revert submission 28659491

Reason for revert: causing merge conflict while reverting curlprit cl ag/27163141 for the regression b/363412105, b/369170606
Reverted changes: /q/submissionid:28659491

Reverted changes: /q/submissionid:28659491

Change-Id: I98b67686fb73a2cfdf7f82f3caafa0c640bff299