settings/styles: Remove redundant rules for `.table-striped thead th`.
settings/styles: Remove redundant rules for `.table-striped thead th`.

This rule is already specified at
 `.settings-section .table-striped thead th`.

punchagan/zulip,rht/zulip,punchagan/zulip,shubhamdhama/zulip,andersk/zulip,zulip/zulip,brainwane/zulip,rht/zulip,punchagan/zulip,shubhamdhama/zulip,timabbott/zulip,kou/zulip,showell/zulip,timabbott/zulip,showell/zulip,zulip/zulip,hackerkid/zulip,punchagan/zulip,eeshangarg/zulip,eeshangarg/zulip,synicalsyntax/zulip,andersk/zulip,rht/zulip,kou/zulip,brainwane/zulip,kou/zulip,andersk/zulip,zulip/zulip,timabbott/zulip,timabbott/zulip,rht/zulip,shubhamdhama/zulip,kou/zulip,synicalsyntax/zulip,brainwane/zulip,timabbott/zulip,shubhamdhama/zulip,zulip/zulip,brainwane/zulip,timabbott/zulip,showell/zulip,brainwane/zulip,eeshangarg/zulip,eeshangarg/zulip,eeshangarg/zulip,punchagan/zulip,hackerkid/zulip,showell/zulip,andersk/zulip,hackerkid/zulip,hackerkid/zulip,zulip/zulip,rht/zulip,showell/zulip,synicalsyntax/zulip,brainwane/zulip,showell/zulip,brainwane/zulip,rht/zulip,kou/zulip,timabbott/zulip,synicalsyntax/zulip,synicalsyntax/zulip,hackerkid/zulip,eeshangarg/zulip,punchagan/zulip,shubhamdhama/zulip,hackerkid/zulip,showell/zulip,synicalsyntax/zulip,rht/zulip,punchagan/zulip,zulip/zulip,hackerkid/zulip,andersk/zulip,eeshangarg/zulip,synicalsyntax/zulip,shubhamdhama/zulip,kou/zulip,andersk/zulip,andersk/zulip,shubhamdhama/zulip,zulip/zulip,kou/zulip