Auto merge of #19628 - tigercosmos:x3, r=KiChjang
Auto merge of #19628 - tigercosmos:x3, r=KiChjang

add note on readme

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Add note about how to use command while running servo
origin  `readme` is not clear.
I think ./mach run [url] [arguments] is more clear than ./mach run [url]

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larsbergstrom/servo,DominoTree/servo,KiChjang/servo,notriddle/servo,pyfisch/servo,avadacatavra/servo,notriddle/servo,nnethercote/servo,upsuper/servo,SimonSapin/servo,sadmansk/servo,SimonSapin/servo,thiagopnts/servo,splav/servo,saneyuki/servo,mattnenterprise/servo,thiagopnts/servo,emilio/servo,mattnenterprise/servo,szeged/servo,peterjoel/servo,sadmansk/servo,sadmansk/servo,avadacatavra/servo,anthgur/servo,emilio/servo,mbrubeck/servo,mbrubeck/servo,avadacatavra/servo,szeged/servo,mattnenterprise/servo,szeged/servo,szeged/servo,ConnorGBrewster/servo,mattnenterprise/servo,thiagopnts/servo,nnethercote/servo,upsuper/servo,pyfisch/servo,emilio/servo,larsbergstrom/servo,cbrewster/servo,splav/servo,avadacatavra/servo,peterjoel/servo,paulrouget/servo,emilio/servo,emilio/servo,SimonSapin/servo,nnethercote/servo,peterjoel/servo,DominoTree/servo,fiji-flo/servo,paulrouget/servo,emilio/servo,larsbergstrom/servo,fiji-flo/servo,pyfisch/servo,szeged/servo,dati91/servo,SimonSapin/servo,peterjoel/servo,szeged/servo,szeged/servo,nnethercote/servo,anthgur/servo,sadmansk/servo,paulrouget/servo,paulrouget/servo,notriddle/servo,szeged/servo,emilio/servo,saneyuki/servo,saneyuki/servo,dati91/servo,splav/servo,splav/servo,peterjoel/servo,upsuper/servo,DominoTree/servo,thiagopnts/servo,ConnorGBrewster/servo,ConnorGBrewster/servo,DominoTree/servo,DominoTree/servo,canaltinova/servo,canaltinova/servo,KiChjang/servo,fiji-flo/servo,mattnenterprise/servo,nnethercote/servo,thiagopnts/servo,mbrubeck/servo,nnethercote/servo,larsbergstrom/servo,peterjoel/servo,DominoTree/servo,paulrouget/servo,KiChjang/servo,avadacatavra/servo,canaltinova/servo,paulrouget/servo,paulrouget/servo,cbrewster/servo,KiChjang/servo,pyfisch/servo,sadmansk/servo,saneyuki/servo,notriddle/servo,fiji-flo/servo,saneyuki/servo,cbrewster/servo,SimonSapin/servo,dati91/servo,peterjoel/servo,notriddle/servo,jimberlage/servo,saneyuki/servo,paulrouget/servo,KiChjang/servo,paulrouget/servo,fiji-flo/servo,szeged/servo,saneyuki/servo,anthgur/servo,fiji-flo/servo,splav/servo,sadmansk/servo,splav/servo,ConnorGBrewster/servo,peterjoel/servo,thiagopnts/servo,mattnenterprise/servo,ConnorGBrewster/servo,canaltinova/servo,anthgur/servo,fiji-flo/servo,cbrewster/servo,mbrubeck/servo,mattnenterprise/servo,cbrewster/servo,splav/servo,pyfisch/servo,DominoTree/servo,thiagopnts/servo,splav/servo,cbrewster/servo,larsbergstrom/servo,SimonSapin/servo,larsbergstrom/servo,anthgur/servo,nnethercote/servo,larsbergstrom/servo,nnethercote/servo,peterjoel/servo,dati91/servo,KiChjang/servo,jimberlage/servo,cbrewster/servo,notriddle/servo,saneyuki/servo,paulrouget/servo,dati91/servo,cbrewster/servo,upsuper/servo,mbrubeck/servo,fiji-flo/servo,avadacatavra/servo,KiChjang/servo,notriddle/servo,nnethercote/servo,avadacatavra/servo,emilio/servo,dati91/servo,pyfisch/servo,upsuper/servo,jimberlage/servo,thiagopnts/servo,mbrubeck/servo,mattnenterprise/servo,anthgur/servo,upsuper/servo,jimberlage/servo,szeged/servo,peterjoel/servo,anthgur/servo,KiChjang/servo,splav/servo,pyfisch/servo,dati91/servo,saneyuki/servo,dati91/servo,KiChjang/servo,anthgur/servo,upsuper/servo,jimberlage/servo,jimberlage/servo,larsbergstrom/servo,saneyuki/servo,pyfisch/servo,ConnorGBrewster/servo,pyfisch/servo,sadmansk/servo,emilio/servo,upsuper/servo,jimberlage/servo,notriddle/servo,larsbergstrom/servo,nnethercote/servo,jimberlage/servo,DominoTree/servo,jimberlage/servo,SimonSapin/servo,sadmansk/servo,emilio/servo,avadacatavra/servo,mbrubeck/servo,ConnorGBrewster/servo,DominoTree/servo,canaltinova/servo,KiChjang/servo,canaltinova/servo,DominoTree/servo,notriddle/servo,notriddle/servo,larsbergstrom/servo,splav/servo,canaltinova/servo,SimonSapin/servo,pyfisch/servo,mbrubeck/servo,canaltinova/servo,ConnorGBrewster/servo