Auto merge of #21499 - PsiACE:add-`gstreamer`-in-`dnf-install`, r=jdm
Auto merge of #21499 - PsiACE:add-`gstreamer`-in-`dnf-install`, r=jdm

Update README.md

add `gstreamer` to `dnf install`

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- [x] These changes not fix #21446, but help to compile.

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larsbergstrom/servo,szeged/servo,szeged/servo,splav/servo,larsbergstrom/servo,nnethercote/servo,szeged/servo,nnethercote/servo,KiChjang/servo,nnethercote/servo,notriddle/servo,DominoTree/servo,emilio/servo,SimonSapin/servo,jimberlage/servo,jimberlage/servo,saneyuki/servo,emilio/servo,sadmansk/servo,KiChjang/servo,pyfisch/servo,jimberlage/servo,SimonSapin/servo,splav/servo,nnethercote/servo,pyfisch/servo,szeged/servo,peterjoel/servo,paulrouget/servo,jimberlage/servo,notriddle/servo,larsbergstrom/servo,KiChjang/servo,paulrouget/servo,KiChjang/servo,saneyuki/servo,emilio/servo,emilio/servo,saneyuki/servo,jimberlage/servo,paulrouget/servo,larsbergstrom/servo,SimonSapin/servo,splav/servo,saneyuki/servo,splav/servo,larsbergstrom/servo,notriddle/servo,SimonSapin/servo,szeged/servo,sadmansk/servo,DominoTree/servo,splav/servo,larsbergstrom/servo,peterjoel/servo,SimonSapin/servo,nnethercote/servo,paulrouget/servo,jimberlage/servo,szeged/servo,pyfisch/servo,KiChjang/servo,DominoTree/servo,larsbergstrom/servo,nnethercote/servo,jimberlage/servo,DominoTree/servo,KiChjang/servo,KiChjang/servo,pyfisch/servo,nnethercote/servo,szeged/servo,larsbergstrom/servo,peterjoel/servo,sadmansk/servo,paulrouget/servo,DominoTree/servo,splav/servo,jimberlage/servo,nnethercote/servo,splav/servo,KiChjang/servo,peterjoel/servo,notriddle/servo,paulrouget/servo,pyfisch/servo,emilio/servo,emilio/servo,nnethercote/servo,szeged/servo,SimonSapin/servo,peterjoel/servo,notriddle/servo,DominoTree/servo,sadmansk/servo,sadmansk/servo,pyfisch/servo,paulrouget/servo,sadmansk/servo,saneyuki/servo,saneyuki/servo,peterjoel/servo,saneyuki/servo,notriddle/servo,saneyuki/servo,emilio/servo,emilio/servo,KiChjang/servo,szeged/servo,larsbergstrom/servo,peterjoel/servo,jimberlage/servo,SimonSapin/servo,emilio/servo,sadmansk/servo,splav/servo,DominoTree/servo,peterjoel/servo,saneyuki/servo,splav/servo,larsbergstrom/servo,SimonSapin/servo,pyfisch/servo,pyfisch/servo,paulrouget/servo,paulrouget/servo,peterjoel/servo,peterjoel/servo,splav/servo,notriddle/servo,szeged/servo,DominoTree/servo,nnethercote/servo,notriddle/servo,sadmansk/servo,saneyuki/servo,emilio/servo,DominoTree/servo,notriddle/servo,DominoTree/servo,pyfisch/servo,notriddle/servo,paulrouget/servo,KiChjang/servo,pyfisch/servo