[stdlib] tempfile and tempdir

[artemiogr97]

Implementation for #2018

[artemiogr97]

I opened the pull to have some feedback, some points to discuss:

• Are the read methods useful in NamedTemporaryFile?
  • personally I don't know in which case I would create a temporary file and read from it at the same time
• should I implement what I need in the os module directly in this pull ?
  • TemporaryDirectory is not implemented yet because os.mkdir and os.rmdir don't exist, I guess shutil.rmtree will be necessary too (implemented in [stdlib] Implement mkdir and rmdir #2430 and [stdlib] Implementation of rmtree #2439)
  • For NamedTemporaryFile there is a slight difference with respect to the python implementation, the name attribute could end up being relative but the functions os.abspath, and os.normpath still don't exist
    • also how different platforms are going to be handled in mojo, in python there are dedicated modules posix and ntpath, I guess the same should be done in mojo?

[artemiogr97]

#2439 must be merged first