Better error reporting/recovery for adjacent JSX elements

[vladima]

Currently code

<p></p>
<p></p>

is effectively parsed as if it was a chain of binary operators

(<p></p>) < p > </ p >

and errors that were reported are not very helpful

tt.tsx(2,4): error TS1109: Expression expected.
tt.tsx(2,8): error TS1109: Expression expected.

Incorrect AST later breaks other LS features like formatting (#5265).

Error in Babel for the same case is much more useful:

Adjacent JSX elements must be wrapped in an enclosing tag