Remove outdated definition of FunctionLiteralBody

[linkrope]

Pull request #2339 added the grammar rule

FunctionLiteralBody:
    SpecifiedFunctionBody

to function.dd, but did not remove the outdated grammar rule

FunctionLiteralBody:
    BlockStatement
    FunctionContractsopt BodyStatement

from expression.dd. The BodyStatement is gone (dead link), so I propose to change the links to FunctionLiteralBody to point to function.dd.

(Alternatively, the grammar rule for FunctionLiteralBody could be moved from function.dd to expression.dd.)

[dlang-bot]

Thanks for your pull request and interest in making D better, @linkrope! We are looking forward to reviewing it, and you should be hearing from a maintainer soon.
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