Set umask 022 before starting prod upgrade.
Set umask 022 before starting prod upgrade.

Follow-on from #2373/ PR https://github.com/zulip/zulip/pull/4316, to set an
appropriate umask also when upgrading so files have appropriate permissions.

I've tested this by starting from a clean install, deleting /srv/* so new
files are downloaded, and then doing an upgrade. It worked starting with both
a current version from master and an older release installed with a less
restrictive umask and then the umask changed.

Fixes #2373.

zulip/zulip,j831/zulip,brainwane/zulip,andersk/zulip,zulip/zulip,timabbott/zulip,dhcrzf/zulip,SmartPeople/zulip,j831/zulip,jackrzhang/zulip,verma-varsha/zulip,vaidap/zulip,brockwhittaker/zulip,brockwhittaker/zulip,andersk/zulip,mahim97/zulip,dhcrzf/zulip,ryanbackman/zulip,punchagan/zulip,showell/zulip,showell/zulip,eeshangarg/zulip,andersk/zulip,showell/zulip,christi3k/zulip,tommyip/zulip,dhcrzf/zulip,verma-varsha/zulip,eeshangarg/zulip,tommyip/zulip,tommyip/zulip,shubhamdhama/zulip,dhcrzf/zulip,amanharitsh123/zulip,kou/zulip,rht/zulip,punchagan/zulip,tommyip/zulip,j831/zulip,zulip/zulip,christi3k/zulip,Galexrt/zulip,synicalsyntax/zulip,verma-varsha/zulip,zulip/zulip,tommyip/zulip,mahim97/zulip,rishig/zulip,Galexrt/zulip,jackrzhang/zulip,vabs22/zulip,brainwane/zulip,rishig/zulip,ryanbackman/zulip,Galexrt/zulip,hackerkid/zulip,rht/zulip,zulip/zulip,eeshangarg/zulip,SmartPeople/zulip,brockwhittaker/zulip,rishig/zulip,jackrzhang/zulip,vaidap/zulip,vaidap/zulip,jphilipsen05/zulip,christi3k/zulip,jphilipsen05/zulip,kou/zulip,kou/zulip,brockwhittaker/zulip,mahim97/zulip,christi3k/zulip,andersk/zulip,eeshangarg/zulip,rht/zulip,rishig/zulip,punchagan/zulip,andersk/zulip,ryanbackman/zulip,timabbott/zulip,j831/zulip,mahim97/zulip,andersk/zulip,kou/zulip,jrowan/zulip,kou/zulip,eeshangarg/zulip,shubhamdhama/zulip,timabbott/zulip,vaidap/zulip,timabbott/zulip,amanharitsh123/zulip,punchagan/zulip,showell/zulip,dhcrzf/zulip,jrowan/zulip,synicalsyntax/zulip,hackerkid/zulip,brainwane/zulip,verma-varsha/zulip,hackerkid/zulip,vaidap/zulip,brainwane/zulip,vabs22/zulip,jphilipsen05/zulip,synicalsyntax/zulip,punchagan/zulip,shubhamdhama/zulip,ryanbackman/zulip,rht/zulip,Galexrt/zulip,amanharitsh123/zulip,jackrzhang/zulip,rishig/zulip,timabbott/zulip,shubhamdhama/zulip,mahim97/zulip,amanharitsh123/zulip,brainwane/zulip,hackerkid/zulip,vabs22/zulip,brockwhittaker/zulip,christi3k/zulip,tommyip/zulip,shubhamdhama/zulip,zulip/zulip,zulip/zulip,brockwhittaker/zulip,rishig/zulip,synicalsyntax/zulip,brainwane/zulip,kou/zulip,hackerkid/zulip,synicalsyntax/zulip,ryanbackman/zulip,j831/zulip,SmartPeople/zulip,vabs22/zulip,rht/zulip,rishig/zulip,showell/zulip,jackrzhang/zulip,jrowan/zulip,eeshangarg/zulip,jphilipsen05/zulip,punchagan/zulip,shubhamdhama/zulip,eeshangarg/zulip,hackerkid/zulip,jrowan/zulip,timabbott/zulip,jphilipsen05/zulip,jackrzhang/zulip,mahim97/zulip,timabbott/zulip,jrowan/zulip,amanharitsh123/zulip,vabs22/zulip,rht/zulip,dhcrzf/zulip,SmartPeople/zulip,andersk/zulip,synicalsyntax/zulip,verma-varsha/zulip,showell/zulip,christi3k/zulip,j831/zulip,jrowan/zulip,hackerkid/zulip,ryanbackman/zulip,vabs22/zulip,brainwane/zulip,Galexrt/zulip,tommyip/zulip,kou/zulip,dhcrzf/zulip,shubhamdhama/zulip,jackrzhang/zulip,showell/zulip,SmartPeople/zulip,jphilipsen05/zulip,Galexrt/zulip,amanharitsh123/zulip,Galexrt/zulip,punchagan/zulip,synicalsyntax/zulip,verma-varsha/zulip,rht/zulip,SmartPeople/zulip,vaidap/zulip