Remove obsolete declarations for buttons on EditMessageComposer on ThreadView (#8632)
Remove obsolete declarations for buttons on EditMessageComposer on ThreadView (#8632)

Those declarations are no longer necessary to align the buttons with the right edge of the input area and background.

Signed-off-by: Suguru Hirahara <4ee41141f41dad19127963eb65a2461cc3bc0d81@users.noreply.github.com>
matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk