Auto merge of #10618 - zwn:fix-windows-build, r=larsbergstrom
Auto merge of #10618 - zwn:fix-windows-build, r=larsbergstrom

Ensure virtualenv activates

Fixes #10595. For more info see #10595 or the commit message.

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avadacatavra/servo,emilio/servo,cbrewster/servo,thiagopnts/servo,nrc/servo,SimonSapin/servo,dsandeephegde/servo,mbrubeck/servo,szeged/servo,anthgur/servo,sadmansk/servo,nnethercote/servo,fiji-flo/servo,cbrewster/servo,szeged/servo,cbrewster/servo,mattnenterprise/servo,peterjoel/servo,rnestler/servo,peterjoel/servo,avadacatavra/servo,ConnorGBrewster/servo,notriddle/servo,sadmansk/servo,jimberlage/servo,DominoTree/servo,anthgur/servo,mattnenterprise/servo,canaltinova/servo,notriddle/servo,nrc/servo,thiagopnts/servo,larsbergstrom/servo,DominoTree/servo,avadacatavra/servo,CJ8664/servo,DominoTree/servo,nrc/servo,rnestler/servo,mbrubeck/servo,paulrouget/servo,thiagopnts/servo,anthgur/servo,peterjoel/servo,emilio/servo,canaltinova/servo,upsuper/servo,szeged/servo,dati91/servo,nnethercote/servo,mbrubeck/servo,emilio/servo,avadacatavra/servo,emilio/servo,jimberlage/servo,larsbergstrom/servo,ConnorGBrewster/servo,pyfisch/servo,nnethercote/servo,dati91/servo,notriddle/servo,DominoTree/servo,saneyuki/servo,KiChjang/servo,nnethercote/servo,dsandeephegde/servo,paulrouget/servo,dati91/servo,CJ8664/servo,paulrouget/servo,splav/servo,nnethercote/servo,anthgur/servo,KiChjang/servo,SimonSapin/servo,larsbergstrom/servo,mbrubeck/servo,splav/servo,peterjoel/servo,mbrubeck/servo,emilio/servo,thiagopnts/servo,eddyb/servo,peterjoel/servo,rnestler/servo,ConnorGBrewster/servo,saneyuki/servo,ConnorGBrewster/servo,CJ8664/servo,notriddle/servo,fiji-flo/servo,canaltinova/servo,peterjoel/servo,pyfisch/servo,ConnorGBrewster/servo,nnethercote/servo,peterjoel/servo,fiji-flo/servo,KiChjang/servo,paulrouget/servo,SimonSapin/servo,nnethercote/servo,sadmansk/servo,avadacatavra/servo,nrc/servo,DominoTree/servo,KiChjang/servo,paulrouget/servo,dati91/servo,rnestler/servo,ConnorGBrewster/servo,peterjoel/servo,thiagopnts/servo,cbrewster/servo,sadmansk/servo,fiji-flo/servo,jimberlage/servo,peterjoel/servo,canaltinova/servo,CJ8664/servo,mattnenterprise/servo,cbrewster/servo,saneyuki/servo,thiagopnts/servo,KiChjang/servo,sadmansk/servo,emilio/servo,fiji-flo/servo,szeged/servo,splav/servo,upsuper/servo,eddyb/servo,splav/servo,eddyb/servo,rnestler/servo,pyfisch/servo,SimonSapin/servo,emilio/servo,mbrubeck/servo,larsbergstrom/servo,rnestler/servo,pyfisch/servo,upsuper/servo,DominoTree/servo,pyfisch/servo,dsandeephegde/servo,eddyb/servo,paulrouget/servo,anthgur/servo,nnethercote/servo,SimonSapin/servo,paulrouget/servo,SimonSapin/servo,notriddle/servo,szeged/servo,eddyb/servo,sadmansk/servo,canaltinova/servo,canaltinova/servo,pyfisch/servo,dsandeephegde/servo,DominoTree/servo,jimberlage/servo,fiji-flo/servo,ConnorGBrewster/servo,splav/servo,mbrubeck/servo,ConnorGBrewster/servo,DominoTree/servo,CJ8664/servo,notriddle/servo,splav/servo,KiChjang/servo,larsbergstrom/servo,szeged/servo,anthgur/servo,splav/servo,thiagopnts/servo,jimberlage/servo,nrc/servo,cbrewster/servo,mattnenterprise/servo,upsuper/servo,notriddle/servo,jimberlage/servo,jimberlage/servo,saneyuki/servo,mbrubeck/servo,eddyb/servo,KiChjang/servo,sadmansk/servo,pyfisch/servo,CJ8664/servo,anthgur/servo,larsbergstrom/servo,fiji-flo/servo,jimberlage/servo,dati91/servo,larsbergstrom/servo,anthgur/servo,notriddle/servo,emilio/servo,larsbergstrom/servo,emilio/servo,CJ8664/servo,emilio/servo,szeged/servo,dsandeephegde/servo,peterjoel/servo,cbrewster/servo,mattnenterprise/servo,pyfisch/servo,notriddle/servo,larsbergstrom/servo,KiChjang/servo,KiChjang/servo,notriddle/servo,mattnenterprise/servo,paulrouget/servo,KiChjang/servo,avadacatavra/servo,upsuper/servo,SimonSapin/servo,paulrouget/servo,eddyb/servo,pyfisch/servo,larsbergstrom/servo,saneyuki/servo,avadacatavra/servo,jimberlage/servo,nnethercote/servo,szeged/servo,dati91/servo,dsandeephegde/servo,CJ8664/servo,dati91/servo,SimonSapin/servo,splav/servo,saneyuki/servo,upsuper/servo,thiagopnts/servo,upsuper/servo,dsandeephegde/servo,splav/servo,rnestler/servo,DominoTree/servo,szeged/servo,canaltinova/servo,mattnenterprise/servo,saneyuki/servo,nrc/servo,saneyuki/servo,saneyuki/servo,szeged/servo,pyfisch/servo,upsuper/servo,saneyuki/servo,rnestler/servo,nnethercote/servo,DominoTree/servo,mattnenterprise/servo,splav/servo,paulrouget/servo,dsandeephegde/servo,fiji-flo/servo,cbrewster/servo,dati91/servo,avadacatavra/servo,canaltinova/servo,eddyb/servo,sadmansk/servo,nrc/servo