docs: use internet archive for isabelle.systems

The isabelle.systems site appears to be down for a while, use archive to
stop the constant PR links failures while we think of a longer-term
solution.

Signed-off-by: Rafal Kolanski <rafal.kolanski@proofcraft.systems>
This commit is contained in:
Rafal Kolanski 2024-08-09 05:03:48 +10:00 committed by Gerwin Klein
parent 2545cfe4a6
commit 0d07f4f3c1
1 changed files with 1 additions and 1 deletions

View File

@ -41,7 +41,7 @@ correct material in here!
circumstances will be transformed into `?x2.0` which is harder to work with),
but don't overuse `'`, i.e. `x'''` is not a good name.
[1]: https://isabelle.systems/conventions/naming.html
[1]: https://web.archive.org/web/20220810201813/https://isabelle.systems/conventions/naming.html
## Directories