mediapc: Limit AV1 framedrop tests to 1080p as per PC14 requirements Frame drop tests for AV1 in PC14 are limited to 1080p instead of 4k. Bug: 287566820 Test: atest CtsMediaPerformanceClassTestCases:FrameDropTest \ CtsMediaPerformanceClassTestCases:AdaptivePlaybackFrameDropTest (cherry picked from https://android-review.googlesource.com/q/commit:51aec035d962e28716142db0c8ba2c2d423f9aa8) Merged-In: I4d6d68bf151fb679d1773391cbc6c95a924b3b2a Change-Id: I4d6d68bf151fb679d1773391cbc6c95a924b3b2a