clang compiler version do not include the latest versions

[strimo378]

Hi all,

I realized that for the clang compiler for every major release only the first update version is available but not the latest one.

E.g. for 17.0.x only 17.0.1 is available but that does not include the latest update version 17.0.6 .

The problem is that compiler explorer is heavily used for reporting bugs and working on outdated update versions gives a wrong picture.

I could imaging that updating the update version poses several challenges:

1. Internally, the clang compiler is identified by the whole version number .e.g. clang1701 for 17.0.1 . Updating clang1701 to clang1706 would invalidate all existing URLs.
2. Keeping all update versions would blow up the docker building.
3. Keeping all update versions would blow up the selection menu.

I suggest to always use the lastest update version, i.e. clang1706 for 17.0, and allow that using clang170x will automatically use clang1706 per default if no other direct matching compiler is installed.

Thank you for effort in creating such a nice product!