[lldb/crashlog] Fix python version requirement issue

In 21a597c3, we fixed a module loading issue by using the new
`argparse.BooleanOptionalAction`. However, this is only available
starting python 3.9 and causes test failures on bots that don't fulfill
this requirement.

To address that, this patch replaces the use of `BooleanOptionalAction`
by a pair of 2 opposite `store` actions pointing to the same destination
variable.

Differential Revision: https://reviews.llvm.org/D158452



Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>