Auto merge of #15104 - avadacatavra:letsencryptauth, r=SimonSapin
Auto merge of #15104 - avadacatavra:letsencryptauth, r=SimonSapin

added lets encrypt authority x3 to trusted roots pem

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servo gave an ssl error on servoexperiments.com because it didn't have the Let's Encrypt X3 authority (https://letsencrypt.org/certificates/)

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- [X ] `./mach build -d` does not report any errors
- [X ] `./mach test-tidy` does not report any errors
- [ X] These changes fix #15087 (github issue number if applicable).

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- [ X] These changes do not require tests because webpage couldn't load before, can now :)

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