Fix magit and git-commit pin deviation

fetch-overrides.nix

@@ -41,5 +41,15 @@
     sly-stepper = "da84e3bba8466c2290c2dc7c27d7f4c48c27b39e";
     # In emacsattic, so shouldn't change underneath us.
     ammonite-term-repl = "b552fe21977e005c1c460bf6607557e67241a6b6";
+
+    # Doom pinned magit to a different revision than git-commit.
+    # They are built from the same repository, which means we require the commits match.
+    #
+    # Doom's pin of magit (cf94190410ef163fd102cdbcb67f28599d31eabc) has the git-commit pin as
+    # parent, and looks like it adds prebuilt documentation for use from Melpa.
+    # Use the git-commit commit, since our derivation should be able to build the documentation.
+    #
+    # TODO: consider allowing git-commit and magit pins to deviate?
+    magit = "55656a31cc4fe6c8996c621f4cf14aa4a1bfe47d";
   };
 }