FCS: `;` token reported as `FSharpTokenKind.SemicolonSemicolon`

[Jand42]

Instead of mapping to FSharpTokenKind.Semicolon, the SEMICOLON token also gets reported via the compiler service as FSharpTokenKind.SemicolonSemicolon

fsharp/src/Compiler/Service/ServiceLexing.fs

Line 1591 in c1b13e3

| SEMICOLON -> FSharpTokenKind.SemicolonSemicolon

while the FSharpTokenKind.Semicolon case remains unused.

Fix is trivial.