gitignore: Fix format for excluding .cache/.
gitignore: Fix format for excluding .cache/.

Comments in gitignore files must be on their own line.

rht/zulip,hackerkid/zulip,dhcrzf/zulip,rishig/zulip,rht/zulip,andersk/zulip,tommyip/zulip,kou/zulip,jackrzhang/zulip,kou/zulip,showell/zulip,timabbott/zulip,timabbott/zulip,rht/zulip,zulip/zulip,dhcrzf/zulip,timabbott/zulip,showell/zulip,andersk/zulip,mahim97/zulip,shubhamdhama/zulip,eeshangarg/zulip,zulip/zulip,punchagan/zulip,punchagan/zulip,showell/zulip,rht/zulip,synicalsyntax/zulip,brainwane/zulip,punchagan/zulip,shubhamdhama/zulip,mahim97/zulip,brainwane/zulip,timabbott/zulip,jackrzhang/zulip,andersk/zulip,brainwane/zulip,showell/zulip,shubhamdhama/zulip,kou/zulip,zulip/zulip,shubhamdhama/zulip,jackrzhang/zulip,mahim97/zulip,rht/zulip,rishig/zulip,punchagan/zulip,dhcrzf/zulip,brainwane/zulip,kou/zulip,tommyip/zulip,dhcrzf/zulip,timabbott/zulip,andersk/zulip,hackerkid/zulip,zulip/zulip,shubhamdhama/zulip,mahim97/zulip,punchagan/zulip,zulip/zulip,tommyip/zulip,rishig/zulip,hackerkid/zulip,kou/zulip,mahim97/zulip,rishig/zulip,dhcrzf/zulip,eeshangarg/zulip,tommyip/zulip,showell/zulip,brainwane/zulip,brainwane/zulip,jackrzhang/zulip,eeshangarg/zulip,showell/zulip,zulip/zulip,hackerkid/zulip,shubhamdhama/zulip,hackerkid/zulip,synicalsyntax/zulip,rishig/zulip,tommyip/zulip,kou/zulip,rishig/zulip,shubhamdhama/zulip,brainwane/zulip,hackerkid/zulip,rht/zulip,tommyip/zulip,eeshangarg/zulip,tommyip/zulip,showell/zulip,jackrzhang/zulip,andersk/zulip,synicalsyntax/zulip,synicalsyntax/zulip,synicalsyntax/zulip,timabbott/zulip,andersk/zulip,eeshangarg/zulip,eeshangarg/zulip,synicalsyntax/zulip,mahim97/zulip,andersk/zulip,rht/zulip,eeshangarg/zulip,kou/zulip,rishig/zulip,dhcrzf/zulip,timabbott/zulip,jackrzhang/zulip,synicalsyntax/zulip,punchagan/zulip,punchagan/zulip,hackerkid/zulip,zulip/zulip,jackrzhang/zulip,dhcrzf/zulip