docs: Shorten some keyboard shortcut descriptions.
docs: Shorten some keyboard shortcut descriptions.

In particular, this fixes some unnecessarily multi-line descriptions
that made the keyboard shortcuts display look bad.

rishig/zulip,shubhamdhama/zulip,verma-varsha/zulip,j831/zulip,Galexrt/zulip,eeshangarg/zulip,rishig/zulip,hackerkid/zulip,mahim97/zulip,synicalsyntax/zulip,vabs22/zulip,rht/zulip,tommyip/zulip,kou/zulip,jphilipsen05/zulip,verma-varsha/zulip,vaidap/zulip,jainayush975/zulip,brockwhittaker/zulip,vaidap/zulip,eeshangarg/zulip,ryanbackman/zulip,showell/zulip,christi3k/zulip,jphilipsen05/zulip,brainwane/zulip,rishig/zulip,andersk/zulip,mahim97/zulip,zulip/zulip,kou/zulip,andersk/zulip,brockwhittaker/zulip,brainwane/zulip,jrowan/zulip,kou/zulip,jrowan/zulip,hackerkid/zulip,dhcrzf/zulip,eeshangarg/zulip,punchagan/zulip,eeshangarg/zulip,brainwane/zulip,SmartPeople/zulip,verma-varsha/zulip,timabbott/zulip,ryanbackman/zulip,kou/zulip,jainayush975/zulip,andersk/zulip,dhcrzf/zulip,Galexrt/zulip,brockwhittaker/zulip,hackerkid/zulip,zulip/zulip,SmartPeople/zulip,jainayush975/zulip,amanharitsh123/zulip,jainayush975/zulip,rht/zulip,aakash-cr7/zulip,synicalsyntax/zulip,dhcrzf/zulip,amanharitsh123/zulip,vaidap/zulip,ryanbackman/zulip,christi3k/zulip,brockwhittaker/zulip,showell/zulip,jackrzhang/zulip,timabbott/zulip,zulip/zulip,andersk/zulip,SmartPeople/zulip,rishig/zulip,SmartPeople/zulip,zulip/zulip,timabbott/zulip,mahim97/zulip,rishig/zulip,synicalsyntax/zulip,j831/zulip,eeshangarg/zulip,punchagan/zulip,showell/zulip,timabbott/zulip,vaidap/zulip,timabbott/zulip,aakash-cr7/zulip,SmartPeople/zulip,ryanbackman/zulip,aakash-cr7/zulip,rht/zulip,jphilipsen05/zulip,timabbott/zulip,amanharitsh123/zulip,showell/zulip,zulip/zulip,christi3k/zulip,mahim97/zulip,jackrzhang/zulip,aakash-cr7/zulip,jackrzhang/zulip,rht/zulip,dhcrzf/zulip,Galexrt/zulip,jackrzhang/zulip,j831/zulip,shubhamdhama/zulip,amanharitsh123/zulip,vabs22/zulip,ryanbackman/zulip,vaidap/zulip,brainwane/zulip,shubhamdhama/zulip,jrowan/zulip,brainwane/zulip,showell/zulip,punchagan/zulip,jrowan/zulip,tommyip/zulip,Galexrt/zulip,kou/zulip,tommyip/zulip,christi3k/zulip,punchagan/zulip,eeshangarg/zulip,mahim97/zulip,christi3k/zulip,shubhamdhama/zulip,andersk/zulip,j831/zulip,vabs22/zulip,vabs22/zulip,kou/zulip,hackerkid/zulip,zulip/zulip,ryanbackman/zulip,eeshangarg/zulip,j831/zulip,hackerkid/zulip,aakash-cr7/zulip,jackrzhang/zulip,brockwhittaker/zulip,brockwhittaker/zulip,hackerkid/zulip,dhcrzf/zulip,hackerkid/zulip,jackrzhang/zulip,verma-varsha/zulip,timabbott/zulip,jrowan/zulip,tommyip/zulip,vabs22/zulip,andersk/zulip,vabs22/zulip,vaidap/zulip,rishig/zulip,rht/zulip,brainwane/zulip,aakash-cr7/zulip,punchagan/zulip,amanharitsh123/zulip,SmartPeople/zulip,punchagan/zulip,kou/zulip,rishig/zulip,Galexrt/zulip,jackrzhang/zulip,shubhamdhama/zulip,shubhamdhama/zulip,jainayush975/zulip,rht/zulip,mahim97/zulip,dhcrzf/zulip,rht/zulip,jphilipsen05/zulip,tommyip/zulip,synicalsyntax/zulip,verma-varsha/zulip,brainwane/zulip,jphilipsen05/zulip,dhcrzf/zulip,synicalsyntax/zulip,shubhamdhama/zulip,showell/zulip,zulip/zulip,tommyip/zulip,j831/zulip,verma-varsha/zulip,jainayush975/zulip,tommyip/zulip,Galexrt/zulip,amanharitsh123/zulip,synicalsyntax/zulip,andersk/zulip,Galexrt/zulip,showell/zulip,christi3k/zulip,jphilipsen05/zulip,jrowan/zulip,synicalsyntax/zulip,punchagan/zulip