LONDON — Britain is opening a new chapter in its military support for Kyiv by inviting companies to develop a new ballistic missile for Ukraine. The move could benefit both countries. The U.K. would get a missile capability its forces currently lack and Ukraine would develop a ballistic missile it doesn't have the cash to finance itself and that could effectively target Russian forces. The U.K. Ministry of Defence announced last week it was launching a contest to have tactical-strike prototypes