maintenance/upload-cache-to-github.py: improve retry logic
maintenance/upload-cache-to-github.py: improve retry logic

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vdsrd/hunter,stohrendorf/hunter,xsacha/hunter,Knitschi/hunter,zhuhaow/hunter,tatraian/hunter,mchiasson/hunter,ErniBrown/hunter,fwinnen/hunter,RomanYudintsev/hunter,madmongo1/hunter,ruslo/hunter,NeroBurner/hunter,NeroBurner/hunter,headupinclouds/hunter,Knitschi/hunter,designerror/hunter,dvirtz/hunter,shekharhimanshu/hunter,NeroBurner/hunter,x10mind/hunter,ErniBrown/hunter,pretyman/hunter,mchiasson/hunter,xsacha/hunter,akalsi87/hunter,dmpriso/hunter,ErniBrown/hunter,ruslo/hunter,vdsrd/hunter,x10mind/hunter,ledocc/hunter,ingenue/hunter,pretyman/hunter,daminetreg/hunter,ikliashchou/hunter,RomanYudintsev/hunter,fire-hunter/hunter,ledocc/hunter,lucmichalski/hunter,caseymcc/hunter,madmongo1/hunter,fire-hunter/hunter,ikliashchou/hunter,zhuhaow/hunter,madmongo1/hunter,headupinclouds/hunter,ingenue/hunter,caseymcc/hunter,pretyman/hunter,shekharhimanshu/hunter,NeroBurner/hunter,akalsi87/hunter,dmpriso/hunter,dan-42/hunter,alamaison/hunter,dvirtz/hunter,lucmichalski/hunter,ingenue/hunter,xsacha/hunter,fwinnen/hunter,alamaison/hunter,isaachier/hunter,ruslo/hunter,alamaison/hunter,zhuhaow/hunter,designerror/hunter,vdsrd/hunter,mchiasson/hunter,daminetreg/hunter,dvirtz/hunter,dmpriso/hunter,pretyman/hunter,designerror/hunter,ErniBrown/hunter,lucmichalski/hunter,dan-42/hunter,ledocc/hunter,ikliashchou/hunter,xsacha/hunter,stohrendorf/hunter,isaachier/hunter,isaachier/hunter,fire-hunter/hunter,tatraian/hunter,headupinclouds/hunter,ikliashchou/hunter,ruslo/hunter,shekharhimanshu/hunter,ingenue/hunter,caseymcc/hunter,tatraian/hunter,fwinnen/hunter,dan-42/hunter,Knitschi/hunter,madmongo1/hunter,stohrendorf/hunter,isaachier/hunter,daminetreg/hunter,akalsi87/hunter,dan-42/hunter,RomanYudintsev/hunter,mchiasson/hunter,x10mind/hunter