Auto merge of #23424 - servo:plugin-search-path, r=ferjm
Auto merge of #23424 - servo:plugin-search-path, r=ferjm

Use correct plugin search path for locally cloned gstreamer

r? @ferjm

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DominoTree/servo,KiChjang/servo,splav/servo,saneyuki/servo,paulrouget/servo,splav/servo,paulrouget/servo,notriddle/servo,splav/servo,KiChjang/servo,nnethercote/servo,pyfisch/servo,larsbergstrom/servo,emilio/servo,nnethercote/servo,notriddle/servo,DominoTree/servo,emilio/servo,larsbergstrom/servo,notriddle/servo,nnethercote/servo,splav/servo,paulrouget/servo,KiChjang/servo,nnethercote/servo,pyfisch/servo,splav/servo,notriddle/servo,notriddle/servo,paulrouget/servo,nnethercote/servo,KiChjang/servo,pyfisch/servo,KiChjang/servo,pyfisch/servo,notriddle/servo,KiChjang/servo,notriddle/servo,splav/servo,larsbergstrom/servo,emilio/servo,saneyuki/servo,nnethercote/servo,emilio/servo,paulrouget/servo,emilio/servo,larsbergstrom/servo,emilio/servo,larsbergstrom/servo,splav/servo,DominoTree/servo,emilio/servo,saneyuki/servo,DominoTree/servo,notriddle/servo,paulrouget/servo,DominoTree/servo,saneyuki/servo,DominoTree/servo,nnethercote/servo,saneyuki/servo,saneyuki/servo,larsbergstrom/servo,pyfisch/servo,saneyuki/servo,saneyuki/servo,nnethercote/servo,KiChjang/servo,pyfisch/servo,paulrouget/servo,DominoTree/servo,pyfisch/servo,saneyuki/servo,KiChjang/servo,pyfisch/servo,DominoTree/servo,larsbergstrom/servo,DominoTree/servo,pyfisch/servo,emilio/servo,nnethercote/servo,nnethercote/servo,larsbergstrom/servo,pyfisch/servo,splav/servo,splav/servo,KiChjang/servo,DominoTree/servo,paulrouget/servo,paulrouget/servo,KiChjang/servo,larsbergstrom/servo,notriddle/servo,splav/servo,emilio/servo,paulrouget/servo,notriddle/servo,emilio/servo,saneyuki/servo,larsbergstrom/servo