Missing preamble from 9.10 release notes
9.8 has a paragraph that goes:
```
The significant changes to the various parts of the compiler are listed in the
following sections. See the `migration guide
<https://gitlab.haskell.org/ghc/ghc/-/wikis/migration/9.8>`_ on the GHC Wiki
for specific guidance on migrating programs to this release.
```
It would be good to have something similar for 9.10
issue