Problem: When multiline semantic token support was introduced, the loop
that finds the end line for a particular token didn't sanitize the token
length sent back by the LSP server. If the server returned an overflowed
length (near uint32 max), neovim would burn cpu and loop for an
extremely long time while trying to find the "end line" represented by
the massively large token, causing neovim to seemingly hang.
Solution: Stop looping once the calculated end_line reaches the actual
last line of the buffer.
Fixes#36257