Everything necessary should be imported when loading (unpickling) either the project or the compiler.

…Python>=3.8

…s imported

Before, we always used the sqlite in-memory database to "disable" the
database. Now, there is a proper configuration option for this. The
advantage is that this can lead to significant performance improvements
when benchbuild is invoked often, for example, in ./configure based
projects. These kinds of projects invoke the wrapped compiler often to
determine whether certain feature are available.

… without module name

"pylint: Command line or configuration file:1: UserWarning: Specifying exception names in the overgeneral-exceptions option without module name is deprecated and support for it will be removed in pylint 3.0. Use fully qualified name (maybe 'builtins.Exception' ?) instead."

- use C yaml loader
- avoid unnecessary parsing in init_from_env()

the parent class yaml.CSafeLoader is implemented in C