Do not release prefix too early

The hotspotPrefix was previously released on line 192, so when a new
prefix was allocated on line 206, it was allowed to "conflict" with the
now-released hotspotPrefix.

This change moves the call to releaseDownstream() to the end, so the
test can properly check for conflicts.

Test: TH
Bug: 375858174
Change-Id: Iac786237340fc14098701d86fa80946a7fb8e0b6
1 file changed