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

Change-Id: Ibf4965aebe4bb6de928e133e1dc4589f239beed7