x/tools/gopls: jump to definition on 'return' should go to the result parameter list

[findleyr]

Frequently, when I'm looking at a return statement, I want to jump to the function signature.

In the category of "more LSP operations should work, more of the time", we could make jump to definition on a return statement go to the result parameter list.

[mateusz834]

This would be also nice for break and continue, maybe goto, but not realy needed, because we can always go to definition of the label (it is required).

[findleyr]

@mateusz834 we can do that too. I think whenever there is an obvious possible result for an LSP operation at a position, we should return it. It is a good UX when more operations work, more of the time.