message-edit-history: Update to new button default style.
message-edit-history: Update to new button default style.

This updates an old button to the new button style.

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