fix(ci): only build devshell on linux

aarch64 darwin has issues building all the postgresql with their
extensions in parallel. `devShell` depends on `start-server` which depends
on the `makePostgresDevSetup`which depends on all databases.

Author: jfroche

nix/checks.nix

@@ -295,7 +295,6 @@
             dbmate-tool
             pg_regress
             ;
-          devShell = self'.devShells.default;
         }
         // pkgs.lib.optionalAttrs (system == "aarch64-linux") {
           inherit (self'.packages)
@@ -312,6 +311,7 @@
             inherit self;
             inherit pkgs;
           };
+          devShell = self'.devShells.default;
         };
     };
 }