bpo-34854: Fix compiling string annotations containing lambdas. (GH-9645)
* Compiling a string annotation containing a lambda with keyword-only
argument without default value caused a crash.
* Remove the final "*" (it is incorrect syntax) in the representation of
lambda without *args and keyword-only arguments when compile from AST.
* Improve the representation of lambda without arguments.
(cherry picked from commit
2a2940e5c3e6d92f4fac5e9d361a1e224bb2f12e)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>