Fix changelog/readme (backport #9935) (#9936)

* Fix changelog/readme

(cherry picked from commit ea0f4640)

* Remove previous release date

---------

Co-authored-by: Francesco Ariis <fa-ml@ariis.it>

Cabal-syntax/ChangeLog.md

-Please see See https://github.com/haskell/cabal/blob/master/release-notes/Cabal-3.10.3.0.md
+Please see https://github.com/haskell/cabal/blob/master/release-notes/Cabal-3.12.0.0.md

Cabal/ChangeLog.md

-# 3.12.0.0 [Francesco Ariis](mailto:fa-ml@ariis.it) March 2024
+# 3.12.0.0 [Francesco Ariis](mailto:fa-ml@ariis.it) May 2024
 * See https://github.com/haskell/cabal/blob/master/release-notes/Cabal-3.12.0.0.md
 
 # 3.10.3.0 [Hécate](mailto:hecate+github@glitchbra.in) January 2024

Cabal/README.md

@@ -34,8 +34,8 @@ Cabal's users what their most pressing problems are with Cabal and
 [Hackage]. You may have a favourite Cabal bug or limitation. Look at
 Cabal's [bug tracker]. Ensure that the problem is reported there and
 adequately described. Comment on the issue to report how much of a
-problem the bug is for you. Subscribe to the issues's notifications to
-discussed requirements and keep informed on progress. For feature
+problem the bug is for you. Subscribe to the issue's notifications to
+discuss requirements and keep informed on progress. For feature
 requests, it is helpful if there is a description of how you would
 expect to interact with the new feature.